TSK · Genesis 16:1

Sarai was barren. She had no child.

Abram said, "Lord Yahweh, what will you give me, since I go childless, and he who will inherit my estate is Eliezer of Damascus?"

God said to Abraham, "Don't let it be grievous in your sight because of the boy, and because of your handmaid. In all that Sarah says to you, listen to her voice. For from Isaac will your seed be called.

Isaac entreated Yahweh for his wife, because she was barren. Yahweh was entreated by him, and Rebekah his wife conceived.

But they had no child, because Elizabeth was barren, and they both were well advanced in years.

These things contain an allegory, for these are two covenants. One is from Mount Sinai, bearing children to bondage, which is Hagar.