John 1:7

7 He came as a witness to testify concerning that light, so that through him all might believe.

Read John 1:7 Using Other Translations

The same came for a witness, to bear witness of the Light, that all men through him might believe.
He came as a witness, to bear witness about the light, that all might believe through him.
to tell about the light so that everyone might believe because of his testimony.