John Calvin Commentary Genesis 26:8

"And it came to pass, when he had been there a long time, that Abimelech king of the Philistines looked out at a window, and saw, and, behold, Isaac was sporting with Rebekah his wife." — Genesis 26:8 (ASV)

Abimelech, king of the Philistines, looked out at a window. Truly admirable is the kind forbearance of God, in not only condescending to pardon the twofold fault of his servant, but in stretching forth His hand and wonderfully averting, by applying a speedy remedy, the evil which he would have brought upon himself.

God did not allow—as had twice occurred to Abraham—his wife to be torn from his embrace; instead, He stirred up a Gentile king to correct his folly mildly and without causing him any trouble. But although God sets before us such an example of His kindness, so that the faithful, if they should ever fall, may confidently hope to find Him gentle and gracious, yet we must beware of complacency when we observe that the holy woman, who was at that time the only mother of the Church on earth, was exempted from dishonor by a special privilege.

Meanwhile, we may surmise from Abimelech's judgment how holy and pure Isaac's conduct had been, upon whom not even a suspicion of evil could fall; and further, how much greater integrity flourished in that age than in our own. For why does he not condemn Isaac as guilty of fornication, since it was probable that some crime was concealed when he disingenuously put forward the title of 'sister' and tacitly denied her to be his wife?

Therefore, I have no doubt that his religion and the integrity of his life served to defend his character. By this example, we are taught to cultivate righteousness throughout our lives, so that people may not be able to suspect anything wicked or dishonorable about us. For there is nothing that will more completely vindicate us from every trace of disgrace than a life lived in modesty and temperance.

We must, however, add, as I have also mentioned before, that lusts were not at that time so commonly and abundantly indulged as to cause a negative suspicion to arise in the king's mind concerning a foreign resident of honest character. Therefore, he easily convinces himself that Rebekah was a wife and not a prostitute.

The chastity of that age is further proved by this: that Abimelech takes the familiar playfulness of Isaac with Rebekah as proof of their marriage. For Moses does not speak about marital intercourse, but about some overly familiar gesture, which was proof of either an immoral display or marital love.

But now licentiousness has so broken through all bounds that husbands are compelled to hear in silence of the immoral conduct of their wives with strangers.