John 1:31

and I knew him not, but, that he might be manifested to Israel, because of this I came with the water baptizing.

Luke 1:17

and he shall go before Him, in the spirit and power of Elijah, to turn hearts of fathers unto children, and disobedient ones to the wisdom of righteous ones, to make ready for the Lord, a people prepared.'

Isaiah 40:3-5

A voice is crying -- in a wilderness -- Prepare ye the way of Jehovah, Make straight in a desert a highway to our God.

Malachi 3:1

Lo, I am sending My messenger, And he hath prepared a way before Me, And suddenly come in unto his temple Doth the Lord whom ye are seeking, Even the messenger of the covenant, Whom ye are desiring, Lo, he is coming, said Jehovah of Hosts.

Malachi 4:2-5

And risen to you, ye who fear My name, Hath the sun of righteousness -- and healing in its wings, And ye have gone forth, and have increased as calves of a stall.

Matthew 3:6

and they were baptized in the Jordan by him, confessing their sins.

Mark 1:3-5

A voice of one calling in the wilderness, Prepare ye the way of the Lord, straight make ye his paths,' --

Luke 1:76-80

And thou, child, Prophet of the Highest Shalt thou be called; For thou shalt go before the face of the Lord, To prepare His ways.

Luke 2:39-42

And when they finished all things, according to the Law of the Lord, they turned back to Galilee, to their city Nazareth;

Luke 3:3-4

and he came to all the region round the Jordan, proclaiming a baptism of reformation -- to remission of sins,

John 1:7

this one came for testimony, that he might testify about the Light, that all might believe through him;

John 1:33

and I did not know him, but he who sent me to baptize with water, He said to me, On whomsoever thou mayest see the Spirit coming down, and remaining on him, this is he who is baptizing with the Holy Spirit;

Acts 19:4

And Paul said, 'John, indeed, did baptize with a baptism of reformation, saying to the people that in him who is coming after him they should believe -- that is, in the Christ -- Jesus;'

Treasury of Scripture Knowledge

Summary

And I knew him not: but that he should be made manifest to Israel, therefore am I come baptizing with water.

Bible References

I knew

John 1:33
and I did not know him, but he who sent me to baptize with water, He said to me, On whomsoever thou mayest see the Spirit coming down, and remaining on him, this is he who is baptizing with the Holy Spirit;
Luke 1:80
And the child grew, and was strengthened in spirit, and he was in the deserts till the day of his shewing unto Israel.
Luke 2:39
And when they finished all things, according to the Law of the Lord, they turned back to Galilee, to their city Nazareth;

But

John 1:7
this one came for testimony, that he might testify about the Light, that all might believe through him;
Isaiah 40:3
A voice is crying -- in a wilderness -- Prepare ye the way of Jehovah, Make straight in a desert a highway to our God.
Malachi 3:1
Lo, I am sending My messenger, And he hath prepared a way before Me, And suddenly come in unto his temple Doth the Lord whom ye are seeking, Even the messenger of the covenant, Whom ye are desiring, Lo, he is coming, said Jehovah of Hosts.
Malachi 4:2
And risen to you, ye who fear My name, Hath the sun of righteousness -- and healing in its wings, And ye have gone forth, and have increased as calves of a stall.
Luke 1:17
and he shall go before Him, in the spirit and power of Elijah, to turn hearts of fathers unto children, and disobedient ones to the wisdom of righteous ones, to make ready for the Lord, a people prepared.'

Therefore

Matthew 3:6
and they were baptized in the Jordan by him, confessing their sins.
Mark 1:3
A voice of one calling in the wilderness, Prepare ye the way of the Lord, straight make ye his paths,' --
Luke 3:3
and he came to all the region round the Jordan, proclaiming a baptism of reformation -- to remission of sins,
Acts 19:4
And Paul said, 'John, indeed, did baptize with a baptism of reformation, saying to the people that in him who is coming after him they should believe -- that is, in the Christ -- Jesus;'