6 So Isaac dwelt in Gerar. 7 And the men of the place asked about his wife. And he said, "She is my sister"; for he was afraid to say, "She is my wife," because he thought, "lest the men of the place kill me for Rebekah, because she is beautiful to behold." 8 Now it came to pass, when he had been there a long time, that Abimelech king of the Philistines looked through a window, and saw, and there was Isaac, showing endearment to Rebekah his wife. 9 Then Abimelech called Isaac and said, "Quite obviously she is your wife; so how could you say, 'She is my sister'?" And Isaac said to him, "Because I said, 'Lest I die on account of her.' " 10 And Abimelech said, "What is this you have done to us? One of the people might soon have lain with your wife, and you would have brought guilt on us." 11 So Abimelech charged all his people, saying, "He who touches this man or his wife shall surely be put to death."

Matthew Henry's Commentary on Genesis 26:6-11

Commentary on Genesis 26:6-11

(Read Genesis 26:6-11)

There is nothing in Isaac's denial of his wife to be imitated, nor even excused. The temptation of Isaac is the same as that which overcame his father, and that in two instances. This rendered his conduct the greater sin. The falls of those who are gone before us are so many rocks on which others have split; and the recording of them is like placing buoys to save future mariners. This Abimelech was not the same that lived in Abraham's days, but both acted rightly. The sins of professors shame them before those that are not themselves religious.