Say unto those bedouin who stayed behind: "In time you will be called upon [to fight] against people of great prowess in war:1 you will have to fight against them [until you die] or they surrender. And then, if you heed [that call], God will bestow on you a goodly reward; but if you turn away as you turned away this time,2 He will chastise you with grievous chastisement."