In approaching the sacrament of Penance, Bonaventure is again sensitive to the different periods of salvation history. “There are two ways of speaking of Penance: either inasmuch as it reconciles to God, or inasmuch as it not only reconciles to God, but also reconciles to the Church.” First, in reconciling to God, it “belongs to the decree of natural law.” He argues that “the Lord both insinuated and instituted [the sacrament of Penance] when he called Adam after his sin in Genesis 3:9, saying ‘Where are you?’” It is of the law of nature that one seeks contrition and forgiveness of sin. And so, Bonaventure holds, God instituted this sacrament even before the written law, when God first called Adam “to return to his heart.”
Second, “to the extent it is a sacrament of the Church, …it had its institution in the written law, whether Mosaic or Evangelical.” In the Mosaic Law the decree of natural law developed in terms of offerings and sacrifices, which “served in place of confession and satisfaction.” However, the sacrament of Penance remained imperfect. Then, “in the New Law, where ecclesiastical unity is perfect and reconciliation is complete,” the sacrament of Penance reached its fullness, always remaining, however, founded initially upon the law of nature.
In the New Law, the fullness of the sacrament of Penance is reached when the Lord instituted, in John 20:22-23, priestly absolution, followed later when “clear and open confession was instituted by the Apostles.” Bonaventure summarizes this historical development of the sacrament of Penance when he writes, “The written law added something beyond what came from natural dictate, and the Gospel Law did not evacuate that added dimension, but rather fulfilled it even more by adding a perfect addition.”
Bonaventure then comes to the question about that perfect addition. He asks, “What is the sign?” or What is the active external signification in this sacrament? To answer this question, his sense of the long history of the institution of this sacrament comes into play. The response to that question is that “external penance naturally represents interior penance.” Interior penance is what is being signified externally—that is, an interior penance already alive and written according to natural law in the heart. “Hence, Penance proceeds outwardly from the interior, and the exterior does not bring about the interior.”
This contrition or return to one’s heart, which reconciles one to God, gives subsequent rise to the external sign of an “exterior humiliation,” whether in disposition or in word. This happens “in the act of contrition and in the accusatory word, and in the penance of satisfaction.” These external signs, in turn, are joined to the form of the word spoken in the absolution of the priest. Several external actions are thus woven together on the part of the two ministers, penitent and priest, both of whom provide the external sign required for the integrity of every sacrament. These conjoined external signs provide thereby the signification for the sacrament of Penance that leads to the final res of the sacrament, perfect contrition and remission of sin.
Bonaventure acknowledges the uniqueness of the external sign found in this sacrament: “…it is in some way caused, namely by coming forth from the interior contrition of heart, and it in some way causes, namely by signifying internal perfect remission of sin. This is because this sacrament is “partially of natural dictate and partly by institution” in both the Mosaic Law and the New Law. This external sign takes its origin from the internal movement of the heart, and it then finds its fulfillment in the interior grace of the remission of sin. Internal reconciliation with God finds itself expressed in reconciliation with the Church, which in turn perfects the initial contrition of heart unto perfect contrition for remission of sin.