Perfection is an impossible standard to reach. This is why almost everyone agrees that they have sinned. And anyone who denies that they have no sin has reached the heights of self-deception. But, when the truth of God’s word takes hold in our heart, the scales fall from our eyes and we see clearly through our denial and self-deception, crying out, “Lord, have mercy upon me, a sinner!”
1 John 1:8
If we say we have no sin, we deceive ourselves, and the truth is not in us.