Genesis 20:12

12 Besides, she really is my sister, the daughter of my father though not of my mother; and she became my wife.

Read Genesis 20:12 Using Other Translations

And yet indeed she is my sister; she is the daughter of my father, but not the daughter of my mother; and she became my wife.
Besides, she is indeed my sister, the daughter of my father though not the daughter of my mother, and she became my wife.
And she really is my sister, for we both have the same father, but different mothers. And I married her.

What does Genesis 20:12 mean?

John Gill's Exposition of the Bible
Genesis 20:12

And yet indeed [she is] my sister
In the same sense as Lot was his brother; for she was sister to Lot, and both were the children of Haran, the brother of Abraham: she [is] the daughter of my father, but not the daughter of my mother;
she was the daughter of his father, being his granddaughter, grandchildren are sometimes called children, but not the daughter or granddaughter of Abraham's mother; Terah having had two wives, by the one he had Haran, the father of Sarah, and by the other Abraham. According to the Arabic writers F6, Abraham and Sarah were the immediate children of Terah, but by two mothers:

``the mother of Abraham (they say) died, whose name was Juna, and Terah married another wife, whose name was Lahazib, some say Tahuitha, who bore him Sarah, afterwards married to Abraham; hence Abraham said, she is my sister on my father's side, but not on my mother's side:''
and she became my wife;
as in those times it was judged lawful, and so it has been accounted lawful in many nations to marry sisters on the father's side, when those on the mother's were prohibited F7.
FOOTNOTES:

F6 Elmacinus, p. 51. Patricides, p. 17. apud Hottinger. Smegma Oriental. p. 281.
F7 Vid. Philo. de Special. Leg. p. 779. Clement. Alex. Stromat. l. 2. p. 421.
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