9 And Abimelech called Abraham and said to him, "What have you done to us? How have I offended you, that you have brought on me and on my kingdom a great sin? You have done deeds to me that ought not to be done." 10 Then Abimelech said to Abraham, "What did you have in view, that you have done this thing?" 11 And Abraham said, "Because I thought, surely the fear of God is not in this place; and they will kill me on account of my wife. 12 But indeed she is truly my sister. She is the daughter of my father, but not the daughter of my mother; and she became my wife. 13 And it came to pass, when God caused me to wander from my father's house, that I said to her, 'This is your kindness that you should do for me: in every place, wherever we go, say of me, "He is my brother." ' "

Matthew Henry's Commentary on Genesis 20:9-13

Commentary on Genesis 20:9-13

(Read Genesis 20:9-13)

See here much to blame, even in the father of the faithful. Mark his distrust of God, his undue care about life, his intent to deceive. He also threw temptation in the way of others, caused affliction to them, exposed himself and Sarah to just rebukes, and yet attempted an excuse. These things are written for our warning, not for us to imitate. Even Abraham hath not whereof to glory. He cannot be justified by his works, but must be indebted for justification, to that righteousness which is upon all and unto all them that believe. We must not condemn all as hypocrites who fall into sin, if they do not continue in it. But let the unhumbled and impenitent take heed that they do not sin on, thinking that grace may abound. Abimelech, being warned of God, takes the warning; and being truly afraid of sin and its consequences, he rose early to pursue the directions given him.