Here’s a nice bit of Kierkegaard:
People are always busy winning disciples. It is of great importance (to themselves!) that they get them quickly. They hasten to use every means to this end, and they quickly reject everyone who is unwilling. God, on the other hand, gains his disciples by long-suffering. He gains them at the very last moment. So it comes about that while men’s disciples fall away at the last moment, God’s disciples stand firm.
This was precisely the case with Peter. Christ gained Peter when he denied him, i.e., at the last moment. And Peter stood firm.