Jesus asks the guards twice who they are looking for. The first time they say "Jesus," he responds with “I am he,” and they fall back to the ground. Here
we see Jesus owning and expressing of his divine power. The second time he responds with “I am he,” it is as a means of liberating his disciples. Our freedom is because of Jesus. Then Peter steps up and strikes the High Priest’s servant. His name is Malchus. Why does that matter?