Paul’s letters rank alongside the Gospel of John as containing the richest vein of trinitarian theology in the New Testament. While the doctrine of the Trinity is not assembled in any one place, and the key terminology for the classical expression of the Trinity (person, substance, etc.) is obviously not present, there are at least three places in his letters that can be described as explicitly trinitarian:1
There are different kinds of gifts, but the same Spirit distributes them. There are different kinds of service, but the same Lord. There are different kinds of working, but in all of them and in everyone it is the same God at work. (1 Cor. 12:4–6)2
May the grace of the Lord Jesus Christ, and the love of God, and the fellowship of the Holy Spirit be with you all. (2 Cor. 13:14)
There is one body and one Spirit, just as you were called to one hope when you were called; one Lord, one faith, one baptism; one God and Father of all, who is over all and through all and in all.
But to each one of us grace has been given as Christ apportioned it. (Eph. 4:4–7)
These three passages offer profound and searching observations about God. They reflect three divine identities, along with a sense of the oneness of God. However, these verses are striking not only for their profound reflections on the doctrine of God, but also because they appear in so-called practical sections of Paul’s epistles. You might have expected Paul’s deepest thinking about Theology Proper to be found in those sections of his letters focused on matters of doctrine and belief. Instead, we find Paul’s descriptions of one loving God the Father, one gracious Lord Jesus Christ, and one generous Holy Spirit, three working together as one for our good in perfect balance and harmony in a discussion of the misuse of the spiritual gifts (1 Cor. 12), in a mundane letter-closing (2 Cor. 13) and in an appeal for unity (Eph. 4) respectively. While there may be many ways into the subject of the Trinity in Paul’s letters, the relationship between his trinitarian thinking and his practical teaching is among the most fascinating, edifying and, at the same time, unexplored angles.
How should we read Paul’s letters in the light of the Trinity? There are two extremes to avoid. First, we must beware of anachronistic interpretation of Paul whereby we read later patristic formulations of the Trinity into his letters. The doctrine of the Trinity is a synthetic judgment about the teaching of all of Scripture rather than a statement found anywhere within it. But equally, we must not adopt a minimalist and non-theological reading of Paul on these matters. E. P. Sanders was right in one sense when he wrote that ‘Paul did not spend his time reflecting on the nature of the deity.’ But Sanders was certainly wrong when he asserted that ‘from Paul we learn nothing new or remarkable about God’.3 Paul did not write about God in abstraction. But that does not mean that a weighty doctrine of God does not emerge from his highly occasional letters.
When noticing and appreciating the doctrine of God in Paul’s letters it is important not to limit Paul’s trinitarian thinking to those passages that explicitly mention the Father, the Son and the Spirit; more subtle textual features such as other names for the three persons of the Godhead,4 the use of terms such as ‘Lord’, the use of pronouns and divine passives5 should not escape our notice. And when reading Paul’s letters, along with observing three distinct divine identities, it is vital to notice the ways in which he affirms their unity and the oneness of God.
We should also not neglect the trinitarian dimensions of Paul’s doctrines of Christ and the Spirit. According to Joseph Fitzmyer, being seized by Christ on the road to Damascus changed Paul’s Christology rather than his Theology Proper.6 However, many of Paul’s discussions of Christology and pneumatology also reflect his understanding of God. In 1 Corinthians 8:6, for example, Paul affirms his belief that Jesus Christ has the status of unique Lord: ‘yet for us there is but one God, the Father, from whom all things came and for whom we live; and there is but one Lord, Jesus Christ, through whom all things came and through whom we live’.
The key words of this verse, namely ‘Lord’, ‘God’ and ‘one’, are taken from Israel’s great Shema, Deuteronomy 6:4 (‘the Lord our God, the Lord is one’), in which Lord and God both refer to the same (one) God. As N. T. Wright observes, in 1 Corinthians 8:6 Paul
has glossed ‘God’ with ‘the Father’, and ‘Lord’ with ‘Jesus Christ’, adding in each case an explanatory phrase: ‘God’ is the Father, ‘from whom are all things and we to him’, and the ‘Lord’ is Jesus the Messiah, ‘through whom are all things and we through him.’7
In 1 Corinthians 8:6 Paul simultaneously reaffirms strict Jewish monotheism and asserts the highest possible Christology imaginable, finding the identity of Christ within the very definition of that one God/Lord of Israel. Many of Paul’s discussions of Christology and the Spirit also have relevance to the Trinity.
Often New Testament scholars, even evangelicals, will only go as far as admitting that Paul engages in ‘unselfconscious trinitarianism’ at best. The problem is that in such a climate we run the risk of not allowing such elements in Paul’s letters to reach anyone’s consciousness.
What, then, are the trinitarian dimensions of Paul’s practical teaching? In the following sections of this chapter we consider his treatments of four practical matters in relation to the Trinity: assurance of salvation, confidence in prayer, intimate fellowship and moral renewal.
Assurance of salvation is a theological problem with keen pastoral dimensions. Even the most committed believers with a good understanding of justification by grace sometimes doubt their own election and salvation. What do we talk about at such times? Does the Trinity come up in such conversations? It is striking how often Paul’s efforts to reassure believers of God’s love are set within a trinitarian framework.
In 1 Corinthians 6 Paul deals with two egregious faults in the church of God in Corinth, namely civil litigation and going to prostitutes. In 1 Corinthians 6:9–10, in the midst of such serious moral failure, Paul warns them that people whose lives are characterized by greed and sexual immorality, and the like, ‘will not inherit the kingdom of God’. Such warnings should not be seen as undermining the eternal security of believers; indeed, they are one means by which God enables believers to persevere. Nonetheless, an unintended effect of strong words of judgment can be to destabilize the confidence of God’s people. Hence in 1 Corinthians 6:11 Paul writes to remind the Corinthian believers of the genuineness of their conversion: ‘And that is what some of you were. But you were washed, you were sanctified, you were justified in the name of the Lord Jesus Christ and by the Spirit of our God.’
To reassure believers in Corinth Paul refers to their washing and forgiveness, positional sanctification and forensic justification. However, we must also notice that the cooperative work of all three persons of the Godhead, to use the language of Chalcedon, is foundational to Paul’s understanding of eternal salvation.8 The terms Paul uses in 1 Corinthians 6:11 also reinforce the eschatological nature of the transformation the Corinthians (along with all other believers in Christ) have experienced. God’s establishment of the Messiah (Christ) as Lord over all and his transformation of his people by the cleansing and renewing power and presence of the Holy Spirit were both part of the Old Testament picture of the wonderful changes that would be introduced with the in-breaking of the age to come and its overcoming of this present evil age.9
As it turns out, when Paul discusses justification by grace through faith as the basis for our assurance, he regularly underscores the roles of the Father, Christ and the Spirit. In Romans 5:1–11 Paul describes the life of those who have been justified and the fruit of that status: ‘Therefore, since we have been justified through faith’ (5:1a). In the face of suffering Paul assures us that ‘God’s love has been poured out into our hearts through the Holy Spirit’ (5:5), a love that is demonstrated beyond any doubt, for ‘Christ died for us’ (5:8; cf. 5:6). In telling the full story of the love of God Paul cannot help but mention the work of Christ and the Spirit. Salvation is the narrative of the saving Trinity’s acting on behalf of human beings.
Likewise, in Titus 3:4–7 the basis of our future hope is having been ‘justified by his grace’ (3:7). Paul states that two facts assure us of the ‘love of God’ (3:4): first, that ‘he saved us, not because of righteous things we had done, but because of his mercy’ (3:5); and second, of ‘the washing of rebirth and renewal by the Holy Spirit, whom he [i.e. God] poured out on us generously through Jesus Christ our Saviour’ (3:5–6). If the collaborative work of God, Jesus Christ and the Holy Spirit in Titus 3:5–6 underscores three distinct divine identities, the unity of God and Christ can be seen in that in Titus 3:4, 6 Paul describes them both as ‘our Saviour’.
In Ephesians 3 Paul is concerned that believers not lose heart over his imprisonment: ‘I ask you, therefore, not to be discouraged because of my sufferings for you’ (3:13). When faced with the discouragement of the experience of suffering, it is natural to doubt God’s love. In this light Paul prays for them in Ephesians 3:14–19:
For this reason I kneel before the Father, from whom every family in heaven and on earth derives its name. I pray that out of his glorious riches he may strengthen you with power through his Spirit in your inner being, so that Christ may dwell in your hearts through faith. And I pray that you, being rooted and established in love, may have power, together with all the Lord’s holy people, to grasp how wide and long and high and deep is the love of Christ and to know this love that surpasses knowledge – that you may be filled to the measure of all the fullness of God.
As in the texts from 1 Corinthians, Romans and Titus (see above), Paul’s encouragement in Ephesians 3:14–19 is set in the context of the joint work of the Father, Christ and the Spirit.10 The prayer is directed to the Father and his petitions include a strengthening in the inner being by the Spirit and in the heart, where Christ dwells. In spite of the reality of suffering, believers can know that they belong to the Lord as his holy people, a status in which strength and power can be found. The final petition is that God’s people would appreciate the love of Christ and be filled with the fullness of God. Both the Spirit and Christ play a role in the heart; and both the Father and Christ are needed for a full experience of God’s love.
Similarly, Romans 8 deals with the ‘present sufferings’ of believers (8:18) and Paul goes to great lengths to reassure them of God’s love in the face of hardship. Romans 8:38–39 concludes that nothing ‘in all creation, will be able to separate us from the love of God that is in Christ Jesus our Lord’. Once again a clearly trinitarian foundation is laid in support of such reassurance. If ‘the Spirit himself testifies with our spirit that we are God’s children’ (8:16), Paul insists that both God and Christ are also on our side:
If God is for us, who can be against us? He who did not spare his own Son, but gave him up for us all – how will he not also, along with him, graciously give us all things? Who will bring any charge against those whom God has chosen? It is God who justifies. Who then is the one who condemns? No one. Christ Jesus who died – more than that, who was raised to life – is at the right hand of God and is also interceding for us. (8:31–34)
Another example of Paul’s conception of the unity and oneness of the Father and the Son can be seen in his description of God’s favourable stance towards us both as ‘the love of Christ’ (8:35) and ‘the love of God’ (8:39). For God to be ‘for us’ (8:31) means that we can be sure of the love of God and Christ; ‘we are more than conquerors through him [Christ] who loved us’ (8:37).
Two more passages may be mentioned as revealing Paul’s consistent pattern of appealing to the harmonious and united work of God, Christ and the Spirit when he points to the security of Christians. First, in 2 Thessalonians 2:13b–14 Paul highlights the past electing work of God, the present sanctifying work of the Spirit and the prospect of sharing the future glory of Jesus Christ: ‘God chose you as firstfruits to be saved through the sanctifying work of the Spirit and through belief in the truth. He called you to this through our gospel, that you might share in the glory of our Lord Jesus Christ.’
And second, in 2 Corinthians 1:21–22 notions of standing firm, being anointed, belonging to God and having a guaranteed future are again predicated on the united threefold work of God, Christ and God’s Spirit: ‘Now it is God who makes both us and you stand firm in Christ. He anointed us, set his seal of ownership on us, and put his Spirit in our hearts as a deposit, guaranteeing what is to come.’
Nothing magnifies grace like appreciating the triune God’s work in salvation. And nothing gives believers more confidence that they are known and loved by God than pointing out the collaborative activity of God, the Lord Jesus Christ and God’s Spirit.
The privilege of prayer is one of the clearest expressions of trinitarian thought in Paul’s letters.11 Yet despite this, many monographs and articles addressing the nature of the Trinity in relation to Paul focus on the question of to whom prayers are directed, rather than the Trinity’s enabling of the act (or fact) of prayer itself. However, within the Pauline corpus several passages detail the impact of the Trinity on prayer. Within the very life of God there is communication. Two aspects of this communication are intercession for the saints and the enabling of their own prayerfulness.
Two of the most concise examples of texts that reflect on prayer and the Trinity appear in Ephesians 2 and Galatians 4. In Ephesians 2 Paul lays out the achievements of Christ in making peace, both peace between us and God, and also peace with each other in bringing Jews and Gentiles together as one body of Christ (Eph. 3:6): ‘For through him [i.e. Christ] we both have access to the Father by one Spirit’ (Eph. 2:18). Possibly Paul’s most liturgical and formulaic utterance about prayer, this verse indicates that we pray to the Father, through the Son, by the Spirit.
The goal of prayer, which the work of the Son and the Spirit enable, is ‘access’ to the Father. The word in question, prosagōgē in Greek, is used just twice more by Paul and appears nowhere else in the New Testament. On both occasions it refers to a secure ‘way of approach’ to God:12
in whom [Christ] we have access to God in boldness and confidence through faith in him [Christ]. (Eph. 3:12 nrsv)
through whom [Christ] we have gained access [to God] by faith into this grace in which we now stand. (Rom. 5:2a)
For Paul prayer is not a ‘hit-and-miss’ affair, like shooting arrows at the moon. We do not pray timidly and uncertainly, blindly hoping that God may hear us. We either have access to God or we do not. And since Christ guarantees our access to God, we come boldly and confidently with the help of the Spirit. Despite being rarely heard as an encouragement to pray, this specifically trinitarian account of the basis for prayer is the most effective inducement to prayer in the Bible.
A similar shape to prayer is evident in Galatians 4:6, ‘Because you are his sons, God sent the Spirit of his Son into our hearts, the Spirit who calls out, “Abba, Father.”’ Climaxing a passage celebrating our adoption into God’s family as his sons and heirs, Paul describes the privilege of addressing God as Father in prayer in trinitarian terms: we pray to our Father through the Spirit of his Son. As in Ephesians 2:18, prayer here is no ‘fingers-crossed’ exercise in uncertain desperation, but a participation in the life of God. The basis for prayer is that ‘God sent the Spirit of his Son into our hearts’. And that Spirit actually prays on our behalf. The same note of grace is struck in the following verses where Paul describes the Galatian Christians as those who now know God, before swiftly correcting himself by saying that a better way of putting it is that God knows us (Gal. 4:8–9; cf. 1 Cor. 8:2).13 This puts the whole business of prayer in a different light, one that is expanded in similar terms in Romans 8.
In Romans 8 Paul is realistic about the difficulty of praying and spells out why praying is so difficult. In response he offers the Trinity as the solution:
In the same way, the Spirit helps us in our weakness. We do not know what we ought to pray for, but the Spirit himself intercedes for us through wordless groans. And he [God] who searches our hearts knows the mind of the Spirit, because the Spirit intercedes for God’s people in accordance with the will of God. (Rom. 8:26–27)
We find it hard to pray because of our weakness and uncertainty as to what to pray (8:26), and because we know neither our own hearts nor the will of God (8:27). Paul’s encouragement to pray is that the Spirit helps us14 in our weakness and makes requests to God on our behalf. The reason the Spirit knows what we need is because God knows both our hearts and the mind of the Spirit. The Spirit then makes our requests in accordance with the will of God, which guarantees that God will grant those requests. If that were not enough, Christ Jesus is also involved in that, along with the Spirit, he also intercedes for us, and from the right hand of God no less (Rom. 8:34).
One could hardly conceive of a more theocentric account of prayer than Romans 8. Being weak, we find it hard to know how to pray. Paul responds that our intercessions are brought to God by (1) the Spirit and (2) Christ Jesus. These intercessions are based on (1) God’s knowing our hearts, (2) God’s knowing the mind of the Spirit and (3) the Spirit’s knowing the will of God. If some parts of Romans 8:26–27 are unclear (e.g. the nature of ‘wordless groans’), one thing is clear: the triune God facilitates our prayers from start to finish.
The life of God as the Trinity and his work within Christians brings about a particular way of life for believers. Paul uses a variety of terms for the life of believers as those who have been reconciled to God and to each other. Indeed, the intimacy of restored relationships, both vertical and horizontal, is a constant refrain in Paul’s letters. And this two-directional fellowship is not some esoteric indulgence, but rather has practical implications for our life together in the service of God.
The famous benediction at the end of 2 Corinthians reveals the trinitarian basis for Paul’s vision of the Christian life: ‘May the grace of the Lord Jesus Christ, and the love of God, and the fellowship of the Holy Spirit be with you all’ (2 Cor. 13:14). Undergirding all of Paul’s instructions to the Corinthians is the work of the triune God. Gordon Fee points out that not only does 2 Corinthians 13:14 contain a solid triadic reference to God, but it also models the intimate fellowship extended from God to the Corinthians. He writes:
The participation in the Holy Spirit continually actualizes that love and grace in the life of the believer and the believing community. The koinonia (‘fellowship/participation in’) of the Holy Spirit is how the living God not only brings people into an intimate and abiding relationship with himself, as the God of all grace, but also causes them to participate in all the benefits of that grace and salvation.15
This fellowship, or participation, extends both to our relationship to God and to each other in the church. There is no autonomous life for the Christian, either horizontally or vertically without reference to the God known in Christ.16
Philippians 2:1–2 likewise grounds our life together in divine blessings:
If then there is any encouragement in Christ, any consolation from [Christ’s] love, any sharing in the Spirit, any compassion and sympathy, make my joy complete: be of the same mind, having the same love, being in full accord and of one mind. (nrsv)
At first blush this passage seems to offer a ‘binitarian’ basis for Christian fellowship: union with Christ and the love of Christ supplemented by ‘sharing in the Spirit’ (koinōnia pneumatos). Here too koinōnia in the Spirit flows out from the vertical aspect of being united with Christ to the horizontal aspect of relationship with others in the body.17
However, a trinitarian basis for Paul’s encouragement to unity and love in Philippians 2:1–2 may also be present. The four ‘if’ clauses contain an implied passive verb, the agency for which is almost certainly God: ‘If there is any encouragement [from God] in Christ, any consolation [from God] from Christ’s love’, and so on. For Paul the most personal and subjective benefits of faith in Christ (encouragement, consolation, sharing, compassion and sympathy), which form the basis for harmonious church life, derive from the work of God, Christ and the Spirit. Elsewhere in Philippians Paul describes believers as those ‘who serve God by his Spirit, who boast in Christ Jesus’ (Phil. 3:3).
In Ephesians 1:17–20 Paul prays that believers may know God, the sure hope and rich inheritance he has given them, as well as God’s great power exemplified in raising Christ from the dead. In order to grasp more fully these spiritual blessings, Paul appeals to the united work of Father, Christ and Spirit: ‘I keep asking that the God of our Lord Jesus Christ, the glorious Father, may give you the Spirit of wisdom and revelation, so that you may know him better’ (Eph. 1:17).
Finally, the qualities of the corporate life of believers that Paul recommends, expressed in joyful praise and thanksgiving and teaching one another, are encapsulated in two well-known passages from the Prison Epistles. In Ephesians 5:18 this life springs from being filled with the Spirit; in Colossians 3:16 it comes from being filled with the word of Christ. In both passages a trinitarian pattern is clearly evident in the descriptions of Christian fellowship. In particular, note in both cases the call to give thanks to God the Father in the name of the Lord Jesus Christ and the heart-felt singing springing from the Spirit:
Do not get drunk on wine, which leads to debauchery. Instead, be filled with the Spirit, speaking to one another with psalms, hymns, and songs from the Spirit. Sing and make music from your heart to the Lord, always giving thanks to God the Father for everything, in the name of our Lord Jesus Christ. (Eph. 5:18–20)
Let the word of Christ dwell among you richly as you teach and admonish one another with all wisdom through psalms, hymns, and songs from the Spirit, singing to God with gratitude in your hearts. And whatever you do, whether in word or deed, do it all in the name of the Lord Jesus, giving thanks to God the Father through him. (Col. 3:16–17 niv modified)
In Romans 14:17–18 Paul responds to the dispute among the Roman Christians concerning kosher food by pointing out there is something far more important than what our stomachs consume:
For the kingdom of God is not a matter of eating and drinking, but of righteousness, peace and joy in the Holy Spirit, because anyone who serves Christ in this way is pleasing to God and receives human approval.
Whereas Paul can speak of the kingdom of God as a future inheritance (as in 1 Cor. 6:9–10; 15:50; Gal. 5:21), here it is a present reality in the life of Christians (as in 1 Cor. 4:20). And the character of this life under God’s rule is described in terms of ‘righteousness, peace and joy’ springing from the Holy Spirit.18 What Paul stresses as vitally important in Romans 14:17 is simply the outworking of our justification and reconciliation to God for our corporate life in the kingdom of God: being declared righteous with God must lead to righteousness in human relationships; finding peace with God must lead to living at peace with others. In other words, the joy of being right with God and Christian hope should spill over into the joy of Christian fellowship. This will lead to living a life that is ‘pleasing to God’, which can also be described in terms of ‘serving Christ’. According to Paul, the corporate life of believers is supported not just by God, but also by Christ and the Holy Spirit.
A fourth aspect of Paul’s practical teaching that has trinitarian dimensions concerns the simple matter of doing good.19 Two texts stand out with respect to the specific language of ‘doing good’ to others, including those outside the church.
First, Galatians 2:19–20 speaks of ‘living for God’ in terms of sharing in the life of Christ:
For through the law I died to the law so that I might live for God. I have been crucified with Christ and I no longer live, but Christ lives in me. The life I now live in the body, I live by faith in the Son of God, who loved me and gave himself for me.
As Miroslav Volf contends, ‘A soteriology based on the indwelling of the Crucified by the Spirit (Galatians 2:19–20) grounds a social practice modeled on God’s passion for the salvation of the world.’20 Paul elaborates on the details of such a life in Galatians 5 in terms of walking by the Spirit (5:16) and exhibiting the fruit of the Spirit (5:22–23). Then in Galatians 6:9–10 he uses the language of ‘doing good’ to reinforce his point: ‘Let us not become weary in doing good, for at the proper time we will reap a harvest if we do not give up. Therefore, as we have opportunity, let us do good to all people . . .’
Along with the role of the Spirit in shaping Christian behaviour we should notice a Christological dimension. Paul’s language of ‘Christ lives in me’ (Gal. 2:20) recalls his frequent description of believers in Christ as those who are ‘in Christ’. Pregnant with meaning, not surprisingly, this phrase has been variously interpreted. If some interpreters have stressed the mystical and experiential sense of the phrase, a religious energy in the soul of the believer, others underscore the eschatological status of being-in-Christ as the mode of existence of God’s new creation (cf. 2 Cor. 5:17: ‘if anyone is in Christ, there is a new creation’ [nrsv]). Charting a middle course, it is best to argue that the emphases on state and status both have some validity, for Christian experience derives from the objective standing of being in Christ. But this happy position is not to be construed privately or individually. In one sense Paul expounds being ‘in Christ’ in 1 Corinthians 12:12–27 with the metaphor of the body of Christ in which all believers are members. To be in Christ is to enjoy both a secure and an objective status before God and a new mode of eschatological existence in solidarity with other believers. The point to note in the context of Paul’s reflections on the shape of the Christian life and the Trinity is that ‘doing good’ is about being conformed to Christlikeness by the power of the Holy Spirit, which is the proper goal of every human life.
In Romans 8:29–30 Paul gives an indication of the goal to which the Christian is heading and the process involved:
For those whom he foreknew he also predestined to be conformed to the image of his Son, in order that he might be the firstborn within a large family. And those whom he predestined he also called; and those whom he called he also justified; and those whom he justified he also glorified. (nrsv)
God’s goal for his children is tied up with Jesus: so that he may have the place of honour among many brothers and sisters; he is also the template to which believers are conformed. Christians can look forward to sharing in his glorification as the end of the process. As Romans 8:17 promises, ‘if children, then heirs, heirs of God and joint heirs with Christ – if, in fact, we suffer with him so that we may also be glorified with him’ (nrsv).
Paul’s practical instructions in Romans 12 – 13 are also driven by this goal of conformity to Christ. Impressive verbal parallels suggest that the transformation insisted upon in 12:1–2 represents a reversal of ‘the downward spiral’ of 1:18–32.21 According to Thompson, ‘underpinning 12.1–2 is Jesus’ foundational and exemplary sacrifice. For Paul, Christ’s image is the goal of the transforming process.’22 This emerges at a number of points. The call for Christians to offer themselves as ‘living sacrifices’ recalls the application of cultic language to Jesus’ atoning death (3:24–25; 5:8–9; 8:3–4) repeatedly in the letter. Where his was necessarily a bloody sacrifice to effect atonement, believers offer a living sacrifice. The language of ‘being transformed’ echoes the goal of conformity to Jesus. The closing verse of the section, Romans 13:14, also suggests that Jesus is in mind as Paul shares his vision of humanity: ‘Instead, put on the Lord Jesus Christ, and make no provision for the flesh, to gratify its desires.’
A second example of Paul’s setting good works in a trinitarian framework can be found in Titus 3:4–8a:
But when the kindness and love of God our Saviour appeared, he saved us, not because of righteous things we had done, but because of his mercy. He [God] saved us through the washing of rebirth and renewal by the Holy Spirit, whom he poured out on us generously through Jesus Christ our Saviour, so that, having been justified by his [God’s] grace, we might become heirs having the hope of eternal life. This is a trustworthy saying. And I want you to stress these things, so that those who have trusted in God may be careful to devote themselves to doing what is good.
The basis for Paul’s appeal that believers be devoted to ‘doing what is good’ is salvation by God’s kindness, love and mercy and justification by God’s grace. Interestingly, both God and Jesus Christ are given the title of ‘Saviour’ (cf. Titus 3:4, 6 above). If the passage affirms that God is the agent of our salvation, we are saved through the washing and rebirth given by the Spirit, who is poured out on us through Jesus Christ. Even in the most mundane and practical of matters, ‘doing good’, Paul offers a thoroughly trinitarian rationale and motivation.
What are the practical implications of the doctrine of the Trinity for Paul in his letters? While this is a good question to ask, it is more in keeping with the nature of Paul and his letters to think about things the other way around: What are the trinitarian dimensions of Paul’s practical teaching? It is not that Paul inherits or arrives at a doctrine of the Trinity in a vacuum, which he then applies in his practical theology. Rather, in following his vocation as a servant and apostle of Jesus Christ to preach the gospel and to instruct believers as to how to conduct their life together in a manner worthy of the gospel he inevitably plumbs the depths of the doctrine of the triune God. While it is possible to talk about assurance of salvation, the act of praying, Christian fellowship and the shape of the Christian life without mentioning the Trinity, this is not the way Paul goes about it. Repeatedly, and to great effect, when Paul deals with matters of pastoral concern, he cannot help but mention the united and collaborative work of God, Christ and the Spirit, three divine identities, who together constitute one God.23
© Brian S. Rosner, 2016