6. Now this it was in Him that John saw, and came to know which he did not know. Not that he did not know Him to be the Son of God, or that he did not know Him to be the Lord, or not know Him to be the Christ; or that he did not know this too, that it was He who should baptize with water and with the Holy Ghost. This he did know; but that he should do this so as to retain the authority to Himself and transfer it to none of His ministers, this is what he learnt in the dove. For by this authority, which Christ has retained to Himself alone, and conferred upon none of His ministers, though He has deigned to baptize by His ministers; by this authority, I say, stands the unity of the Church, which is figured in the dove, concerning which it is said, “My dove is one, the only one of her mother.” For if, as I have already said, my brethren, the authority were transferred by the Lord to His minister, there would be as many baptisms as ministers, and the unity of baptism would no longer exist.