Church Fathers on Mark 1:8

According to the above-mentioned prophecy of Isaiah, the way of the Lord is prepared by John, through faith, baptism, and penitence; the paths are made straight by the rough marks of the hair-cloth garment, the girdle of skin, the feeding on locusts and wild honey, and the most lowly voice; whence it is said, 'John was in the wilderness.'

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 sins [ed. note: vol 1, p. 97, note A]. For the 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.

The baptism of John had not remission of sins, but only brought men to penitence. He preached therefore the baptism of repentance, that is, he preached that to which the baptism of penitence led, namely, remission of sins, that they who in penitence received Christ, might receive Him to the remission of their sins.