It’s Jesus who brings his disciples and asks them a life-changing question: “Who do you say that I am?” One of the disciples, Simon, answers correctly: “You are the Christ, the Son of the living God.” Jesus then responds:
Blessed are you, Simon Bar-Jona! For flesh and blood has not revealed this to you, but my Father who is in heaven. And I tell you, you are Peter, and on this rock I will build my church, and the gates of Hades shall not prevail against it. I will give you the keys of the kingdom of heaven, and whatever you bind on earth shall be bound in heaven, and whatever you loose on earth shall be loosed in heaven.
There are two important details to recognize right now. First, it is Jesus who reveals to Simon his deepest identity as Saint Peter. But related to this is a second point: only after Simon declares Jesus to be “the Son of the living God” does Jesus declare Simon to be “the son of Jonah,” which is what “Bar-Jona” means. In other words, the question of “Who am I?” can be accurately answered only by first answering “Who is Jesus?”