Genesis 20:4-6

"Now Abimelech had not come near her: and he said, Lord, wilt thou slay even a righteous nation? Said he not himself unto me, She is my sister? and she, even she herself said, He is my brother: in the integrity of my heart and the innocency of my hands have I done this. And God said unto him in the dream, Yea, I know that in the integrity of thy heart hast thou done this, and I also withheld thee from sinning against me: therefore suffered I thee not to touch her."

It is important to note that Abimelech had also heard of the destruction of the whole nation of the Sodomites and feared that the same thing might befall his people. How otherwise can we account for his use of the word "nation" in his petition? Note also that he believed in the true God as having control over the nations, not merely one nation, and that he considered that God to be righteous and fair in his treatment of men.

Another thing of particular interest is the fact that God had struck an entire household (a very great one) with a serious and potentially fatal disease for the specific purpose of preventing a sin against his purpose. A similar instance is the sudden death of Herod recorded in Acts 12.

The "integrity" and "innocence" of Abimelech are restricted in meaning to his conduct and intentions toward Sarah. Abimelech was better than some men, but there is no hint here of his being sinless.