everlasting covenant through offspring from Isaac
Everlasting Covenant Through Offspring From Isaac
Genesis 17:19 And (KJV) God said, Sarah thy wife shall bear thee a son indeed; and thou shalt call his name Isaac: and I will establish my covenant with him for an everlasting covenant, and with his seed after him.
Romans 9:7 Neither, because they are the seed of Abraham, are they all children: but, In Isaac shall thy seed be called.