John Chrysostom
Catena Aurea · Johannesevangelium 1
There was a man sent from God, whose name was John. The same came for a witness, to bear witness of the Light, that all men through him might believe. He was not that Light, but was sent to bear witness of that Light.
(Hom. vi. [v.] c. 1) After this esteem nothing that he says as human; for he speaketh not his own, but his that sent him. And therefore the Prophet calls him a messenger, I send My messenger, (Mal. 3:1) for it is the excellence of a messenger, to say nothing of his own. But the expression, was sent, does not mean his entrance into life, but to his office. As Esaias was sent on his commission, not from any place out of the world, but from where he saw the Lord sitting upon His high and lofty throne; (Isai. 6:1.) in like manner John was sent from the desert to baptize; for he says, He that sent me to baptize with water, thesame said unto me, Upon Whom thou shalt see the Spirit descending, and remaining on Him, the same is He which baptizeth with the Holy Ghost. (John 1:33)