After the crucifixion, Peter had failed as a follower of Jesus. Rather than remaining by Jesus’ side until His death on the cross, Peter had fled, and then denied ever having known Jesus. He had thoroughly abandoned his teacher. What else could he do but go back to the life he knew before Jesus had called him? He certainly couldn’t claim to be a disciple anymore.
“Simon Peter said to them, ‘I am going fishing.’ They said to him, ‘We will go with you.’ They went out and got into the boat, but that night they caught nothing.” -John 21:3 (ESV)
Peter went back to being a fisherman, but now he was even failing at what he used to do for a living. He had failed as a disciple, and he had failed as a fisherman. He got into the boat, went back to his old business of fishing, and he caught nothing.
So is it surprising that Peter dives into the sea and swims when he sees Jesus standing on the shore? What other chance does he have to be useful for anything? Only when he was with Jesus had Peter ever been useful. Jesus made Peter come alive in a way that nothing else ever had or ever could. When Peter was with Jesus, Peter had a purpose. Jesus had been building something great with Peter and the other disciples, and Peter craved the sense of purpose he had known as a disciple of the One true God. He must have remembered what Jesus had told him:
“You are Peter, and on this rock I will build my church, and the gates of hell shall not prevail against it.” -Matthew 16:18 (ESV)
So, although he was “stripped for work,” Peter “threw himself into the sea.” Only Jesus had ever made Peter come alive with excitement and purpose. Without Jesus, Peter was just a failure, plodding through life as a common fisherman.
The same is true of me. Jesus has made me come alive in a way nothing else ever has or ever could. The same can be true for you and for every other person. Without Jesus, we have no purpose. We fail at life. Only He can make us come alive. Only He can give us purpose. So why would we want to keep plodding through life and toiling away and catching nothing? We need to leave behind anything worldly that we think is important. I need Jesus, you need Jesus, and everyone else needs Jesus. He can build us into a rock, and even the gates of hell cannot stop us from doing His work.