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 the covenant in a mass circumcision. His father Abram, given the new name "Abraham," then 99, was circumcised along with the others (). At the time of the covenant, God informed Abraham that his wife Sarah would give birth to a son, whom he was instructed to name Isaac. God told Abraham that He would establish his covenant through Isaac, and when Abraham inquired as to Ishmael's role, God answered that Ishmael has been blessed and that He "will make him fruitful, and will multiply him exceedingly; twelve princes shall he beget, and I will make him a great nation."