Who has testified to and vouched for all that he saw [in his visions], the word of God and the testimony of Jesus Christ.
who bare record of the word of God, and of the testimony of Jesus Christ, and of all things that he saw.
who bare witness of the word of God, and of the testimony of Jesus Christ, even of all things that he saw.
who bore witness to the word of God and to the witness of Jesus Christ, including all that John saw.
he has offered testimony to the Word of God, and whatever he saw is the testimony of Jesus Christ.