I indeed have baptized you with water: but he shall baptize you with the Holy Spirit.
All Commentaries on Mark 1:8 Go To Mark 1
Theophylact of Ochrid
AD 1107
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.
Or else; The garment of "camel's hair” was significative of grief, for John pointed out, that he who repented should mourn. For sackcloth signifies grief; but the girdle of skins hews the dead state of the Jewish people. The food also of John not only denotes abstinence, but also shows forth the intellectual food, which the people then were eating, without understanding any thing lofty, but continually raising themselves on high, and again sinking to the earth. For such is the nature of locusts, leaping on high and again falling. In the same way the people ate honey, which had come from bees, that is, from the prophets; it was not however domestic, but wild, for the Jews had the Scriptures, which are as honey, but did not rightly understand them.
Some persons also understand it thus; all who came to John, and were baptized, through penitence were loosed from the bands of their sins by believing in Christ. John then in this way loosed the shoe-latchet of all the others, that is, the bands of sin. But Christ's shoe-latchet he was not able to unloose, because he found no sin in Him.