We accept human testimony, but God's testimony is greater because it is the testimony of God, which he has given about his Son. (NIV)
If we accept [as we do] the testimony of men [if we are willing to take human authority], the testimony of God is greater (of stronger authority), for this is the testimony of God, even the witness which He has borne regarding His Son. (AMP)
If we receive the witness of men, the witness of God is greater: for this is the witness of God which he hath testified of his Son. (KJV)