John 1:8

He was not that light, but was sent to bear witness of the light.

John 1:20

he confessed, and denied not; but declared openly, I am not the Christ.

John 3:28

Ye your selves bear me witness, that I said, I am not the Christ, but am sent before Him.

Acts 19:4

Then said Paul, John indeed baptized with the baptism of repentance, telling the people, that they should believe in Him that was coming after him, that is, in Christ Jesus.

Treasury of Scripture Knowledge

Summary

He was not that Light, but was sent to bear witness of that Light.

General references

Bible References

That light

John 1:20
he confessed, and denied not; but declared openly, I am not the Christ.
John 3:28
Ye your selves bear me witness, that I said, I am not the Christ, but am sent before Him.
Acts 19:4
Then said Paul, John indeed baptized with the baptism of repentance, telling the people, that they should believe in Him that was coming after him, that is, in Christ Jesus.

General references

Mark 11:30
The baptism of John, was it from heaven, or from men? answer me.
Acts 13:24
John having preached before his coming the baptism of repentance to all the people of Israel.