Mark 1:3

A voice of one crying in the wilderness, Prepare the way of the Lord! Make his paths straight.

Matthew 3:3

For this is he that was spoken of by Isaiah the prophet, saying; A voice of one crying in the wilderness, Prepare the way of the Lord, make his paths straight.

Luke 3:4-6

as it is written in the book of the words of Isaiah the prophet; A voice of one crying in the wilderness, prepare the way of the Lord, make his paths straight.

John 1:15

John testified of him, and cried, saying, This is the one of whom I said, He that comes after me existed before me, for he was before me.

John 3:28-36

You yourselves bear me witness, that I said, I am not the Christ, but am sent before him.

John 1:19-34

AND this is the testimony of John, when the Jews from Jerusalem sent priests and Levites to ask him, Who are you?

Treasury of Scripture Knowledge

Summary

The voice of one crying in the wilderness, Prepare ye the way of the Lord, make his paths straight.

Bible References

General references

Matthew 3:3
For this is he that was spoken of by Isaiah the prophet, saying; A voice of one crying in the wilderness, Prepare the way of the Lord, make his paths straight.
Luke 3:4
as it is written in the book of the words of Isaiah the prophet; A voice of one crying in the wilderness, prepare the way of the Lord, make his paths straight.
John 1:15
John testified of him, and cried, saying, This is the one of whom I said, He that comes after me existed before me, for he was before me.
John 3:28
You yourselves bear me witness, that I said, I am not the Christ, but am sent before him.