The Birth of Isaac
As promised, Sarah had a son and they named him Isaac. Abraham's slave Hagae had a son Ishmael and Sarah demanded they be sent away and not to share in the inheritance.
So while he was worried about his son, he sent Hagar and the boy from their land. Hagar and the boy wandered in the desert until the water Abraham was gone. God heard the boy crying and conforted Hagar by telling her that this son would make a nation. Then God provided a well for them to drink from. The boy grew up in the desert of Parah and became an archer.
Isaac means "he laughs" but it was Abraham and Sarah who were laughing at the good fortune of having a son so late in their lives. Since God chose Isaac's name this indicated God likes also to laugh. We are made in His image.
In the New Testament (Galatians 4:22-33) Paul turns this event into an allegory. According to Biblegate.com, Paul's view was used to link Hagar to Judaism, on the basis that the slave Hagar represented bondage to the "old law", which the Christian dispensation had supplanted. In this respect Jews were seen, spiritually speaking, as descendants of Hagar, not Sarah. The equation of Jews with descendents of Hagar was also used to justify the subordination of Jews in medieval Christian kingdoms, and even their expulsion, on the model of the subjection and expulsion of Hagar.
"In the Scriptures we learn that Abraham had two sons. The mother of one of them was a slave, while the mother of the other one had always been free. The son of the slave woman was born in the usual way. But the son of the free woman was born because of God's promise. All of this has another meaning as well. Each of the two women stands for one of the agreements God made with his people. Hagar, the slave woman, stands for the agreement that was made at Mount Sinai. Everyone born into her family is a slave. Hagar also stands for Mount Sinai in Arabia and for the present city of Jerusalem. She and her children are slaves. But our mother is the city of Jerusalem in heaven above, and she isn't a slave. The Scriptures say about her, "You have never had children, but now you can be glad. You have never given birth, but now you can shout. Once you had no children, but now you will have more children than a woman who has been married for a long time."
My friends, you were born because of this promise, just as Isaac was. But the child who was born in the natural way made trouble for the child who was born because of the Spirit. The same thing is happening today. The Scriptures say, "Get rid of the slave woman and her son! He won't be given anything. The son of the free woman will receive everything." My friends, we are children of the free woman and not of the slave.