Luke 1:13-20
But the angel said to him, "Do not be afraid Zacharias, for your earnest prayer has been heard. Your wife Elizabeth will give birth to a son and you will name him John.
Romans 9:6-9
But it is not as if the word of God [i.e., His promise to Israel] has failed [in its fulfillment]. For not all those descended from the Israelites are [truly] Israelites [i.e., God's people].
Galatians 4:28-31
Now, brothers, you [Christians] are children of the promise [made to Abraham. See 3:29] just like Isaac, [Abraham's son] was.
Treasury of Scripture Knowledge
Summary
And 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.
General references
Bible References
General references
Luke 1:55
to Abraham and his descendants forever."