John 1:7-9, 15-17, 29, 34

This man came as a witness, to testify about the Light, so that all might believe [in Christ, the Light] through him. John was not the Light, but came to testify about the Light. There it was—the true Light [the genuine, perfect, steadfast Light] which, coming into the world, enlightens everyone. [Is 49:6]

John testified [repeatedly] about Him and has cried out [testifying officially for the record, with validity and relevance], “This was He of whom I said, ‘He who comes after me has a higher rank than I and has priority over me, for He existed before me.’ ” For out of His fullness [the superabundance of His grace and truth] we have all received grace upon grace [spiritual blessing upon spiritual blessing, favor upon favor, and gift heaped upon gift]. For the Law was given through Moses, but grace [the unearned, undeserved favor of God] and truth came through Jesus Christ. [Ex 20:1]

The next day he saw Jesus coming to him and said, “Look! The Lamb of God who takes away the sin of the world! [Ex 12:3; Is 53:7]

I myself have [actually] seen [that happen], and my testimony is that this is the Son of God!”