Mark 1:4

John was baptising in the wilderness, and preaching the baptism of repentance for the remission of sins.

Luke 1:77

to give the knowledge of salvation to his people, by the remission of their sins,

Matthew 3:1-2

THEN in those days came John the Baptist, preaching in the desert country of Judea,

Matthew 3:6

and were baptized by him in Jordan, on making confession of their sins.

Matthew 3:11

I indeed baptize you with water unto repentance: but he that is coming after me is mightier than I, whose sandals I am not worthy to carry: he shall baptize you with the Holy Spirit, and with fire:

Luke 3:2-3

when Annas and Caiaphas were high-priests, the word of God came to John the son of Zacharias in the wilderness;

John 3:23

Now John also was baptising at Enon, near to Salem, for there were many streams of water there: and they came, and were baptised.

Acts 10:37

even that which was the common talk through all Judea, beginning from Galilee, after the baptism which John preached;

Acts 13:24-25

John having preached before his first coming the baptism of repentance to all the people of Israel.

Acts 19:3-4

And he asked them, Into what then were ye baptised? And they replied, Into John's baptism.

Acts 22:16

And now why delay? arise, to be baptised, and wash away thy sins, calling upon the name of the Lord.

Treasury of Scripture Knowledge

Summary

John did baptize in the wilderness, and preach the baptism of repentance for the remission of sins.

Remission

Bible References

Did

Matthew 3:1
THEN in those days came John the Baptist, preaching in the desert country of Judea,
Luke 3:2
when Annas and Caiaphas were high-priests, the word of God came to John the son of Zacharias in the wilderness;
John 3:23
Now John also was baptising at Enon, near to Salem, for there were many streams of water there: and they came, and were baptised.
Acts 10:37
even that which was the common talk through all Judea, beginning from Galilee, after the baptism which John preached;
Acts 13:24
John having preached before his first coming the baptism of repentance to all the people of Israel.
Acts 19:3
And he asked them, Into what then were ye baptised? And they replied, Into John's baptism.

Remission

Acts 22:16
And now why delay? arise, to be baptised, and wash away thy sins, calling upon the name of the Lord.