Origen
Catena Aurea · Johannesevangelium 1
And they which were sent were of the Pharisees. And they asked him, and said unto him, Why baptizest thou then, if thou he not that Christ, nor Elias, neither that prophet? John answered them, saying, I baptize with water: but there standeth one among you, whom ye know not; He it is, who coming after me is preferred before me, whose shoe’s latchet I am not worthy to unloose. These things were done in Bethabara beyond Jordan, where John was baptizing.
(in Joan. tom. vi. c. 15) Or thus; Having said, I indeed baptize with water, in answer to the question, Why baptizest thou then?—to the next, If thou be not Christ? he replies by declaring the preexistent substance of Christ; that it was of such virtue, that though His Godhead was invisible, He was present to every one, and pervaded the whole world; as is conveyed in the words; There standeth one among you. For He it is, Who hath diffused Himself through the whole system of nature, insomuch that every thing which is created, is created by Him; All things were made by Him. Whence it is evident that even those who enquired of John, Why baptizest thou then? had Him among them. Or, the words, There standeth one among you, are to be understood of mankind generally. For, from our character as rational beings, it follows that the words exists in the centre of us, because the heart, which is the spring of motion within us, is situated in the centre of the body. Those then who carry the word within them, but are ignorant of its nature, and the source and beginning and the way in which it resides in them; these, hearing the word within them, know it not. But John recognised Him, and reproached the Pharisees, saying, Whom ye know not. For, though expecting Christ’s coming, the Pharisees had formed no lofty conception of Him, but supposed that He would only be a holy man: wherefore he briefly refutes their ignorance, and the false ideas that they had of His excellence. He saith, standeth; for as the Father standeth, i. e. exists without variation or change, so standeth the Word ever in the work of salvation, though It assume flesh, though It be in the midst of men, though It stand invisible. Lest any one however should think that the invisible One Who cometh to all men, and to the universal world, is different from Him Who was made man, and appeared on the earth, he adds, He that cometh after me; i. e. Who will appear after me. The after however here has not the same meaning that it has, when Christ calls us after Him; for there we are told to follow after Him, that by treading in His steps, we may attain to the Father; but here the word is used tointimate what should follow upon John’s teaching; for he came that all may believe, having by his ministry been fitted gradually by lesser things, for the reception of the perfect Word. Therefore he saith, He it is Who cometh after me.