Bede the Venerable
Catena Aurea · Markusevangelium 1
John did baptize in the wilderness, and preach the baptism of repentance for the remission of sins. And there went out unto him all the land of Judæa, and they of Jerusalem, and were all baptized of him in the river of Jordan, confessing their sins. And John was clothed with camel’s hair, and with a girdle of a skin about his loins; and he did eat locusts and wild honey; And preached, saying, There cometh one mightier than I after me, the latchet of whose shoes I am not worthy to stoop down and unloose. I indeed have baptized you with water: but he shall baptize you with the Holy Ghost.
(in Marc. i. 2) It is evident that John not only preached, but also gave to some the baptism of repentance; but he could not give baptism for the remission of sinsc. For remission of sins is only given to us by the baptism of Christ. It is therefore only said, Preaching the baptism of repentance for the remission of sins; for he preached a baptism which could remit sins, since he could not give it. Wherefore as he was the forerunner of the Incarnate Word of the Father, by the word of his preaching, so by his baptism, which could not remit sins, he preceded that baptism, of penitence, by which sins are remitted.