Luke 1:13-20

But the angel said to him: Fear not, Zachariah; for your prayer is heard, and your wife Elizabeth shall bear you a son, and you shall call his name John.

Romans 9:6-9

It is not possible that the word of God has failed; for they are not all Israel who are of Israel.

Galatians 4:28-31

We, indeed, brethren, like Isaac, are children of promise.

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
by remembering his mercy to Abraham and to his posterity forever.