The finale of the Sermon on the Mount. Jesus makes the same point here as in his instructions to the scribe who elicits the parable of the Good Samaritan: the only way you can take his teaching to heart is to live it.
“Everyone who hears what I say and does it is like a man who built his house upon rock; and the rain fell and the floods came and the winds blew and beat against that house, and it didn’t fall, because it was founded on rock. And everyone who hears what I say and doesn’t do it is like a man who built his house upon sand; and the rain fell and the floods came and the winds blew and beat against that house, and it fell; and great was its fall.”
who hears what I say and does it: Jesus’ brother James (or one of James’s disciples), in his compassionate and telling criticism of Paul’s teaching about faith and works, says,
What good is it, my dear friends, for someone to say that he has faith when he doesn’t act as if he loves God? Can his faith save him? If a fellow human being is naked and hungry, and you say to him, “Keep warm, eat well,” and don’t give him what he needs, what good is that? So faith, if it doesn’t lead to action, is dead. (James 2:14ff.)
source: Matthew 7:24-27, Luke 6:47-49