Matthew Henry Commentary Genesis 20:1-8

"And Abraham journeyed from thence toward the land of the South, and dwelt between Kadesh and Shur. And he sojourned in Gerar. And Abraham said of Sarah his wife, She is my sister. And Abimelech king of Gerar sent, and took Sarah. But God came to Abimelech in a dream of the night, and said to him, Behold, thou art but a dead man, because of the woman whom thou hast taken. For she is a man`s wife. 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 thou has done this, and I also withheld thee from sinning against me. Therefore suffered I thee not to touch her. Now therefore restore the man`s wife. For he is a prophet, and he shall pray for thee, and thou shalt live. And if thou restore her not, know thou that thou shalt surely die, thou, and all that are thine. And Abimelech rose early in the morning, and called all his servants, and told all these things in their ear. And the men were sore afraid." — Genesis 20:1-8 (ASV)

Deceitful conduct will not prosper: it brings ourselves and others into danger. God warns Abimelech of his danger of sin, and his danger of death for his sin. Every willful sinner is spiritually dead, but Abimelech pleads ignorance.

If our consciences testify that, even though we may have been deceived into a trap, we have not knowingly sinned against God, this will be our source of joy in the day of adversity. It is a source of comfort to those who are honest that God knows their honesty and will acknowledge it. It is a great mercy to be prevented from sinning; for this, God must receive the glory.

But if we have ignorantly done wrong, that will not excuse us if we knowingly persist in it. Anyone who does wrong, whoever they are, prince or peasant, will certainly receive the due recompense for the wrong they have committed, unless they repent and, if possible, make restitution.