1 John 1:8

If we say, "We have no sin," we are deceiving ourselves and the truth is not in us.

James 3:2

For in many respects we often stumble. If any man never stumbles in speech, the same is a perfect man, able to bridle the whole body as well.

1 John 2:4

He who says, "I know Him," but does no continue obeying his commandments, is a liar,

Romans 3:23

since all have sinned and lack the glory which comes from God;

1 Corinthians 3:18

Let no one deceive himself. If any one of you supposes that he is wise in the philosophy of the present age, let him become foolish, so that he may be wise.

Galatians 6:3

If a man fancies himself to be somebody when he is really nobody he is deceiving himself.

1 Timothy 6:5

and wrangling between men whose minds are corrupt and destitute of the truth; who suppose that godliness is a source of gain.

2 Timothy 3:13

But wicked men and impostors will go on from bad to worse, deceiving others, and being themselves deceived.

James 1:22

And become doers of the Word, and not merely hearers, deceiving yourselves.

James 1:26

If a man thinks himself to be religious, and yet does not bridle his tongue, but deceives his own religion,

2 Peter 2:13

suffering wrong as the wage of wrong which they have done. These are men who count it pleasure to carouse in open daylight; they are spots and blemishes reveling in their deceit, even while they are feasting with you.

1 John 1:6

If we say, "We have partnership with Him," when we are passing our life in the darkness, we are lying and are not doing the truth.

1 John 1:10

If we say, "We have not sinned," we are making him a liar, and his word is not in us.

1 John 3:5-6

And you know that he was manifested to take away sins; and in him is no sin.

2 John 1:2

I love you for the sake of the truth which is abiding in us and will be with us forever.

3 John 1:3

For I was glad when brothers came and bore testimony to your truth, as indeed you are passing your life in truth.

Treasury of Scripture Knowledge

Summary

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

General references

Bible References

Say

1 John 1:6
If we say, "We have partnership with Him," when we are passing our life in the darkness, we are lying and are not doing the truth.
1 John 3:5
And you know that he was manifested to take away sins; and in him is no sin.
Romans 3:23
since all have sinned and lack the glory which comes from God;
James 3:2
For in many respects we often stumble. If any man never stumbles in speech, the same is a perfect man, able to bridle the whole body as well.

We deceive

1 Corinthians 3:18
Let no one deceive himself. If any one of you supposes that he is wise in the philosophy of the present age, let him become foolish, so that he may be wise.
Galatians 6:3
If a man fancies himself to be somebody when he is really nobody he is deceiving himself.
2 Timothy 3:13
But wicked men and impostors will go on from bad to worse, deceiving others, and being themselves deceived.
James 1:22
And become doers of the Word, and not merely hearers, deceiving yourselves.
2 Peter 2:13
suffering wrong as the wage of wrong which they have done. These are men who count it pleasure to carouse in open daylight; they are spots and blemishes reveling in their deceit, even while they are feasting with you.

General references

Hebrews 8:12
For I will have mercy upon their wrong-doings, And their sins I will remember no more."