John 6:20

Jesus identified Himself by saying literally "I am" (Gr. ego eimi). This is sometimes a way Jesus described Himself as God, as John recorded Jesus’ words (e.g., John 8:24). However the clause does not always mean that since it is the normal way of identifying oneself (cf. John 9:9). In those instances the translation, "It is I," gives the intended meaning. Here Jesus was just identifying Himself to the disciples, though obviously someone who could walk on water was more than a mere man.