The question of Jesus' authority is answered by a fourfold witness: 1) John the Baptist, 2) the signs or miracles, 3) the Father, and 4) the Scriptures. All four of these witnesses defend Jesus' identity. Jesus does not need human confirmation for his claims because His testimony is self-attesting, but He provides the witnesses so that His hearers may be changed. The primary testimony is the Spirit's. There is nothing more ultimate by which to authenticate God.
