If we say we have no sin, we deceive ourselves, and the truth is not in us. If we confess our sins, he is faithful and just, and will forgive our sins and cleanse us from all unrighteousness.

The Bible (The New Testament) (AD 1st - 2nd C) Christian sacred scripture

1 John 1:8-9 [KJV (1611)]
    (Source)

Alternate translations:

If we say we have no sin in us, we are deceiving ourselves and refusing to admit the truth; but if we acknowledge our sins, then God who is faithful and just will forgive our sins and purify us from everything that is wrong.
[Jerusalem (1966)]

If we say that we have no sin, we deceive ourselves, and there is no truth in us. But if we confess our sins to God, he will keep his promise and do what is right: he will forgive us our sins and purify us from all our wrongdoing.
[GNT (1976)]

If we say that we have no sin, we deceive ourselves, and the truth is not in us. If we confess our sins, he who is faithful and just will forgive us our sins and cleanse us from all unrighteousness.
[NRSV (1989)]