John Calvin Commentary Genesis 20:9

"Then Abimelech called Abraham, and said unto him, What hast thou done unto us? And wherein have I sinned against thee, that thou hast brought on me and on my kingdom a great sin? Thou hast done deeds unto me that ought not to be done." — Genesis 20:9 (ASV)

Then Abimelech called Abraham. There are those who suppose that the king of Gerar did not make a complaint against Abraham, but rather declared his own repentance. If, however, we fairly weigh his words, we find confession mixed with expostulation. Although he complains that Abraham had acted unjustly, he still does not transfer the blame to him so completely as to free himself from all fault.

And he may justly impute part of the blame to Abraham, as he does, provided he also acknowledges his own sin. Let us therefore know that this king did not act as hypocrites are in the habit of doing. For, as soon as a pretext is provided for blaming others, they confidently absolve themselves; they even regard it as a lawful justification for themselves if they can draw others into participation in their crime.

But Abimelech, while he complains that he had been deceived and had been misled by such imprudence, still does not, meanwhile, hesitate to condemn himself as guilty of a great sin. ‘It is not because of you,’ he says, ‘that I and my whole kingdom were prevented from falling into the greatest wickedness.’ No one, therefore, can exonerate himself from blame on the pretext that he was induced by others to sin.

It is, however, to be noted that adultery is here called a great sin because it involves not one man only, but a whole people, as in a common crime. The king of Gerar could not, indeed, have spoken this way had he not acknowledged the sacred right of marriage. But, at the present time, Christians—at least those who boast of the name—are not ashamed to jokingly downplay so great a crime, from which even a heathen shrinks with the greatest horror.

Let us, however, know that Abimelech was a true herald of that divine judgment, which miserable men try in vain to evade with their quibbles. And let that expression of Paul always come to our minds: Be not deceived; because of those things cometh the wrath of God upon the disobedient (1 Corinthians 5:9; Ephesians 5:6). It is not without reason that he makes this sin common to the whole nation, for when crimes are committed with impunity, a whole region is, in a certain sense, polluted.

And it is especially well-known that the anger of God is provoked against the whole body of the people through the king. Hence, with all the greater earnestness and care, we must beseech God to govern by his Spirit those whom he has placed in authority over us, and then, to preserve the country in which he has granted us a dwelling-place, exempt and pure from all iniquity.