Theophany

Why then is this day called Theophany? Because Christ made Himself known to all -- not then when He was born -- but then when He was baptised. Until this time He was not known to the people. And that the people did not know Him, Who He was, listen about this to John the Baptist, who says: "Amidst you standeth, Him Whom ye know not of" (Jn.1:26). And is it surprising that others did not know Him, when even the Baptist did not know Him until that day? "And I -- said he -- knew Him not: but He that did send me to baptise with water, about This One did tell unto me: over Him that shalt see the Spirit descending and abiding upon Him, This One it is Who baptiseth in the Holy Spirit" (Jn. 1:33).

~St. John Chrysostom, "Discourse On the Day of the Baptism of Christ"