Bible: Genesis 17:21; 21:12-13

17:21 But I will establish my covenant with Isaac, whom Sarah will bear to you at this set time next year.”
21:12 But God said to Abraham, “Do not be upset 1  about the boy or your slave wife. Do 2  all that Sarah is telling 3  you because through Isaac your descendants will be counted. 4  21:13 But I will also make the son of the slave wife into a great nation, for he is your descendant too.”

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