But he who was of the slave woman was born according to the flesh, but he of the free woman through the promise.
But what does it say? “The word is near you, in your mouth and in your heart.” This is the word of faith that we preach:
For it is written that Abraham had two sons, the one by a slave woman, the other by a free woman.
By faith Sarah herself also received the ability to conceive seed, and she bore a child when she was past the age, because she judged Him faithful who had promised.