Who bare record of the word of God, and of the testimony of Jesus Christ, and of all things that he saw.
who testifies to everything he saw — that is, the word of God and the testimony of Jesus Christ.
ὃς ἐμαρτύρησεν τὸν λόγον τοῦ Θεοῦ καὶ τὴν μαρτυρίαν Ἰησοῦ Χριστοῦ, ὅσα εἶδεν.
os emartyrēsen ton logon toy Theoy kai tēn martyrian Iēsoy Christoy, osa eiden.