¹² But God said to him, “Do not be so distressed about the boy and your slave woman. Listen to whatever Sarah tells you, because it is through Isaac that your offspring^[a] will be reckoned.^(A)

¹⁸ even though God had said to him, “It is through Isaac that your offspring will be reckoned.”^[a](A)

¹⁹ Then God said, “Yes, but your wife Sarah will bear you a son,^(A) and you will call him Isaac.^[a](B) I will establish my covenant with him^(C) as an everlasting covenant^(D) for his descendants after him.

⁷ Nor because they are his descendants are they all Abraham’s children. On the contrary, “It is through Isaac that your offspring will be reckoned.”^{[a](A) 8} In other words, it is not the children by physical descent who are God’s children,^(B) but it is the children of the promise who are regarded as Abraham’s offspring.^(C)