Philip the Arab and Christianity that appear—save for one reference to Ishmael—figure in the political history of the first three centuries of the Christian era. To Eusebius, the Saracens of the 4th century are direct-line descendants of the biblical Ishmaelites, descendants of the handmaid, Hagar, and the patriarch, Abraham. They are thus outcasts, beyond God's Covenant with the favored son of Abraham, Isaac. The twin images of the Ishmaelite and the Saracen—outcasts and "latrones", raiders of the frontiers—reinforce each other and give Eusebius' portrait of the Arab nation an unhappy color. He may have been reluctant to associate the first Christian emperor with a people
Ishmael Abraham to expel Ishmael and his mother, saying: "Get rid of that slave woman and her son, for that slave woman's son will never share in the inheritance with my son Isaac." Her demand was painful for Abraham, who loved Hagar and Ishmael. Abraham agreed only after God told him that "in Isaac your seed shall be called", and that God would "make a nation of the son of the bondwoman" Ishmael, since he was a descendant of Abraham (), God having previously told Abraham "I will establish My covenant with [Isaac]," while also making promises concerning the Ishmaelite nation