If we claim to be without sin, we deceive ourselves and the truth is not in us. (NIV)

If we say we have no sin [refusing to admit that we are sinners], we delude and lead ourselves astray, and the Truth [which the Gospel presents] is not in us [does not dwell in our hearts]. (AMP)

If we say that we have no sin, we deceive ourselves, and the truth is not in us. (KJV)