Say to the desert Arabs who lagged behind: "Ye shall be summoned (to fight) against a people given to vehement war: then shall ye fight, or they shall submit. Then if ye show obedience, Allah will grant you a goodly reward, but if ye turn back as ye did before, He will punish you with a grievous Penalty."
Say to those who remained behind of the bedouins, "You will be called to [face] a people of great military might; you may fight them, or they will submit. So if you obey, Allah will give you a good reward; but if you turn away as you turned away before, He will punish you with a painful punishment."