wild asses - (Job 11:12). So Ishmael is called a “wild ass-man”; Hebrew (Gen 16:12). These Bedouin robbers, with the unbridled wildness of the ass of the desert, go forth thither. Robbery is their lawless “work.” The desert, which yields no food to other men, yields food for the robber and his children by the plunder of caravans.
rising betimes - In the East travelling is begun very early, before the heat comes on.