Mark 1:4

John came (egeneto Iwanhv). His coming was an epoch (egeneto), not a mere event (hn). His coming was in accordance with the prophetic picture (kaqwv, Mark 1:2). Note the same verb about John in John 1:6. The coming of John the Baptizer was the real beginning of the spoken message about Christ. He is described as

the baptizing one (o aptizwn) in the wilderness (en th erhmw). The baptizing took place in the River Jordan (Mark 1:5, Mark 1:9) which was included in the general term the wilderness or the deserted region of Judea.

Preached the baptism of repentance (khrusswn baptisma metanoiav). Heralded a repentance kind of baptism (genitive case, genus case), a baptism marked by repentance. See on Matthew 3:2 for discussion of repent, an exceedingly poor rendering of John's great word metanoiav. He called upon the Jews to change their minds and to turn from their sins, "confessing their sins" (ecomologoumenoi tav amartiav autwn). See Matthew 3:16. The public confessions produced a profound impression as they would now.

Unto remission of sins (eiv afesin amartiwn). This is a difficult phrase to translate accurately. Certainly John did not mean that the baptism was the means of obtaining the forgiveness of their sins or necessary to the remission of sins. The trouble lies in the use of eiv which sometimes is used when purpose is expressed, but sometimes when there is no such idea as in Matthew 10:41 and Matthew 12:41. Probably "with reference to" is as good a translation here as is possible. The baptism was on the basis of the repentance and confession of sin and, as Paul later explained (Romans 6:4), was a picture of the death to sin and resurrection to new life in Christ. This symbol was already in use by the Jews for proselytes who became Jews. John is treating the Jewish nation as pagans who need to repent, to confess their sins, and to come back to the kingdom of God. The baptism in the Jordan was the objective challenge to the people.