Paul returns again to an example from the Jewish Scriptures, from the Law itself, to show the Galatians that they are the children of God, true heirs of Abraham, not slaves. Paul uses the stories of Hagar, the slave-woman of Abraham, and Sarah, his wife, in an allegorical way such as was used by the Jewish rabbis to interpret Scripture. Paul shows Hagar as illustrating the slavery of the Jewish people to the Law. Her son, Ishmael, was not Abraham's heir; Ishmael was the child of his mother's slavery. Isaac, the son born as a result of God's promise, was the heir. Paul understands the two women as illustrating the two covenants, the Old and the New. Hagar stands for the old covenant of Sinai and the Jewish people enslaved to the Law. Sarah illustrates the heavenly Jerusalem, a metaphor for the Christian Church, freed from the Law. The Church is the new people of God, the people of the new Covenant. The members of God's Church are like the son of Sarah and Abraham who was born as a result of God's promise. Paul quotes Genesis 21:10 to show that those who are still slaves to the Law will have no place in the Kingdom of God. He is referring to Jews who have rejected the Good News. This severe judgement is based on their own Scriptures.