Luke 3:3

And John went through the whole district of the Jordan, proclaiming baptism upon repentance, for the forgiveness of sins.

Luke 1:77

To give his people the knowledge of salvation In the forgiveness of their sins,

Matthew 3:5-6

At that time Jerusalem, and all Judea, as well as the whole district of the Jordan, went out to him

Matthew 3:11

I, indeed, baptize you with water to teach repentance; but He who is Coming after me is more powerful than I, and I am not fit even to carry his sandals. He will baptize you with the Holy Spirit and with fire.

Mark 1:4-5

And in fulfillment of this, John the Baptizer appeared in the Wilderness, proclaiming a baptism upon repentance, for the forgiveness of sins.

John 1:28

All this took place at Bethany, across the Jordan, where John was then baptizing.

John 1:31-33

I myself did not know him, but, that he may be made known to Israel, I have come, baptizing with water."

John 3:26

And the disciples came to John and said: "Rabbi, the man who was with you on the other side of the Jordan, and to whom you have yourself borne testimony--he, also, is baptizing, and everybody is going to him."

Acts 13:24

John having first proclaimed, before the appearance of Jesus, a baptism upon repentance for all the people of Israel.

Acts 19:4

"John's baptism was a baptism upon repentance," rejoined Paul, "and John told the people (speaking of the 'One Coming; after him) that they should believe in him--that is in Jesus."

Acts 22:16

And now why wait any longer: Be baptized at once, wash away your sins, and invoke his Name.

Treasury of Scripture Knowledge

Summary

And he came into all the country about Jordan, preaching the baptism of repentance for the remission of sins;

For

Bible References

The country

Matthew 3:5
At that time Jerusalem, and all Judea, as well as the whole district of the Jordan, went out to him
Mark 1:4
And in fulfillment of this, John the Baptizer appeared in the Wilderness, proclaiming a baptism upon repentance, for the forgiveness of sins.
John 1:28
All this took place at Bethany, across the Jordan, where John was then baptizing.
John 3:26
And the disciples came to John and said: "Rabbi, the man who was with you on the other side of the Jordan, and to whom you have yourself borne testimony--he, also, is baptizing, and everybody is going to him."

Preaching

Matthew 3:6
And were baptized by him in the river Jordan, confessing their sins.
Mark 1:4
And in fulfillment of this, John the Baptizer appeared in the Wilderness, proclaiming a baptism upon repentance, for the forgiveness of sins.
John 1:31
I myself did not know him, but, that he may be made known to Israel, I have come, baptizing with water."
Acts 13:24
John having first proclaimed, before the appearance of Jesus, a baptism upon repentance for all the people of Israel.
Acts 19:4
"John's baptism was a baptism upon repentance," rejoined Paul, "and John told the people (speaking of the 'One Coming; after him) that they should believe in him--that is in Jesus."
Acts 22:16
And now why wait any longer: Be baptized at once, wash away your sins, and invoke his Name.

For

Luke 1:77
To give his people the knowledge of salvation In the forgiveness of their sins,