The painting of Hagar, the daughter of Pharaoh and the second wife of Abraham, shows her in a deeply shadowed desert landscape, turned, so she cannot see the imminent death from thirst, of her son, Ishmael. As narrated in Genesis, Ishmael and Hagar have been sent out of Abraham's house into the wilderness, but as Ishmael lay dying, an angel appears to save him and to tell Hagar that he will become a great nation. The lunette shows two houses -- one of Ishmael, the progenitor of the Arab nations, and the other of Isaac, the ancestor of the Jews. They are both the sons of Abraham, but the conflict between them which began in their childhood, separates them through the centuries, so that even their shadows fall in opposite directions. (http://janetshafner.com/biblical-visions/Hagar.jpg.php)