Mark 1:3

The voice of one crying in the wilderness, Make ready 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: The 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, saying: The voice of one crying in the wilderness, Make ready the way of the Lord, make his paths straight;

John 1:15

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

John 3:28-36

You yourselves will testify for me, that I said, I am not the Christ, but that I am sent before him.

John 1:19-34

And this is the testimony of John, when the Jews sent priests and Levites from Jerusalem 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: The 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, saying: The voice of one crying in the wilderness, Make ready the way of the Lord, make his paths straight;
John 1:15
John testified of him, and cried, saying: This is he of whom I said: He that comes after me, is now before me, for he existed before me.
John 3:28
You yourselves will testify for me, that I said, I am not the Christ, but that I am sent before him.