John 18:6 New English Translation

⁶So when Jesus^[a] said to them, “I am he,” they retreated^[b] and fell to the ground.^[c]

John 18:6 tn Grk “he”; the referent (Jesus) has been specified in the translation for clarity.
John 18:6 tn Grk “moved back” (but here a fairly rapid movement is implied).
John 18:6 sn When Jesus said to those who came to arrest him “I am,” they retreated and fell to the ground. L. Morris says that “it is possible that those in front recoiled from Jesus’ unexpected advance, so that they bumped those behind them, causing them to stumble and fall” (John [NICNT], 743-44). Perhaps this is what in fact happened on the scene, but the theological significance given to this event by the author implies that more is involved. The reaction on the part of those who came to arrest Jesus comes in response to his affirmation that he is indeed the one they are seeking, Jesus the Nazarene. But Jesus makes this affirmation of his identity using a formula which the reader has encountered before in the Fourth Gospel, e.g., 8:24, 28, 58. Jesus has applied to himself the divine Name of Exod 3:14, “I AM.” Therefore this amounts to something of a theophany which causes even his enemies to recoil and prostrate themselves, so that Jesus has to ask a second time, “Who are you looking for?” This is a vivid reminder to the reader of the Gospel that even in this dark hour, Jesus holds ultimate power over his enemies and the powers of darkness, because he is the one who bears the divine Name.

New English Translation (NET)