In today's Scripture lesson we listen to Peter deny Jesus. Peter denies Jesus three times. This betrayal seems even worse when we consider how Peter had boasted earlier: "Lord, why can’t I follow you now? I will lay down my life for you.” (John 13:37 NIV)
Of course Jesus knew better. He knew what people were like. He knew that Peter would turn his back on him.
Before the resurrection Peter is the poster-boy for unredeemed humanity. He may aspire to be loyal and faithful. But he will give up these aspirations when it comes down to saving his own skin.
This however, is not the whole story.
If Peter is the poster-boy for unredeemed humanity, he is also the poster-boy for how Jesus transforms people. After Jesus' death and resurrection Peter is reinstated by Jesus. And Peter becomes an extremely important figure in the new Christian community. He delivers a powerful sermon at Pentecost, performs a number of healings and miracles, and it is his testimony that is largely responsible for the inclusion of the Gentiles in the growing Christian community.
Peter is also arraigned by the Sanhedrin and put into prison by Herod. He is threatened, flogged, and chained (see Acts 4:7-22, 5:18-42, 12:1ff). The Bible doesn't tell us about the end of his ministry, but tradition tells us that Peter was martyred by Nero, crucified upsidedown because he didn't consider himself worthy of dying in the same manner as his Lord.
Before Jesus' death Peter was the poster-boy for unredeemed humanity. After Jesus' resurrection Peter is an example of a redeemed humanity, that does accomplishes amazing things in the power of God's Spirit. In the end Peter will keep that extraordinary promise of laying his life down for Jesus, but only because Jesus has already laid down his life for Peter.