'Freewoman' in the Bible

For it is written that Abraham had two sons, one by a slave and the other by a free woman.

But the one by the slave was born according to the impulse of the flesh, while the one by the free woman was born as the result of a promise.

But what does the Scripture say?Drive out the slave and her son, for the son of the slave will never be a coheir with the son of the free woman.

Therefore, brothers, we are not children of the slave but of the free woman.