Charles Ellicott Commentary John 1:49

"Nathanael answered him, Rabbi, thou art the Son of God; thou art King of Israel." — John 1:49 (ASV)

You are the Son of God.—Recognition breeds recognition. He had felt that strange Presence as a spiritual power that animated hope and thought, made the prophets’ words living truths, and filled the current beliefs about the Messiah with true meaning. Yes, it permeates him completely once more. It is there before him. Rabbi, You are the Son of God; You are the King of Israel. (For these titles as existing in the Messianic expectation of the day, compare John 11:27; John 12:13; John 12:15; Matthew 26:63; Mark 3:11; Mark 5:7. See also the note on the quotation from Zechariah in Matthew 21:5.)