Passage Genesis 12:19
Two points are made about Abraham. The first concerns marriage. When Pharaoh rebukes Abram in Genesis 12:19 for saying “She is my sister” so that he took her as his wife, and Abraham admits in Genesis 20:12 that Sarah really is his sister, his father’s daughter, who became his wife, the Bible is shown telling this without embarrassment. Genesis 16:3 adds that Sarah gave Hagar to Abraham “as a wife”. These are the patriarchs held up as models of faith, and their household arrangements are told plainly and without comment.
The second point is a promise that did not come true as stated. God promises Abraham and his offspring all the land of Canaan as an everlasting possession in Genesis 17:8, and says the same in Genesis 13:15 and Exodus 32:13. Yet Acts 7:5 says God gave him no inheritance in it, not even a foot’s length. The question put is how an everlasting gift can be said to be given to a man who never owned any of it.
Besides, she is indeed my sister, the daughter of my father though not the daughter of my mother, and she became my wife.
Genesis 20:12
And I will give to you and to your offspring after you the land of your sojournings, all the land of Canaan, for an everlasting possession, and I will be their God.”
Genesis 17:8
Source: see Credits and references (no. 2, p. 4).