Similarities between John 6, John 21, and even John 2 show that when Christ tells Peter to ‘feed my sheep,’ he means something far beyond bread. What Peter is to give, like Christ himself, is his very life for the sheep.
The stage is set with James before turning to the sharp confrontation at Antioch, where Paul corrects Peter to his face. Paul’s letters to the Thessalonians and his wider second missionary journey follow, the same gospel integrity worked out in new territory.
Peter’s faith is heroic before it is mature, still shaped by an earthly, millennial hope rather than true understanding. Jesus corrects it directly at the transfiguration, then turns in chapter 18 to teach the humility that heroic faith still lacks.