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." (16)
Tafsir
Those who had shown weakness on the occasion of Hudaybiyah were deprived of the reward resulting therefrom, but still the door was not closed to them, because the campaign to promote Monotheism was to face many difficult situations. They were told that if they proved that they were imbued with the spirit of sacrifice on future occasions, they would once again be entitled to the Grace of God. A test of this kind decides whether a man is a believer or a hypocrite. Only those who have some real difficulty are exempt from it. God pardons an error forced on a person because of circumstances which are beyond his control. But any other kind of shortcoming is not pardonable in the eyes of God.
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