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 son to help him build the requested Kaaba. Islamic traditions hold that the Kaaba was first built by Adam and that Abraham and Ishmael rebuilt the Kaaba on the old foundations. As Ishmael grew up in Arabia, he is said to have become fluent in Arabic. In the genealogical trees that the early scholars drew, Ishmael was considered the ancestor of the Northern Arabs and Muhammad was linked to him through the lineage of the patriarch Adnan. Ishmael may also have been the ancestor of the Southern Arabs through his descendant Qahtan. In the book of Galatians (4:21–31), Paul uses