Say, I pray you, that you are my sister: that it may be well with me for your sake; and my soul shall live because of you.
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George Leo Haydock
My sister. This was no lie; because she was his niece, being daughter to his brother Aran, and therefore, in the style of the Hebrews, she might truly be called his sister; as Lot is called Abraham's brother. (Genesis xiv. 14.) See Genesis xx. 12. (Challoner)
Others say, Sarai was the half-sister of Abraham, by another mother. (Haydock)