That Allāh may reward the truthful for their truth and punish the hypocrites if He wills or accept their repentance. Indeed, Allāh is ever Forgiving and Merciful.
So that Allah rewards the truthful who fulfilled what they promised Allah, by virtue of their truth and fulfilling their promises, and punish the hypocrites who broke their promises if He wishes, by making them die before they repent from their disbelief, or by accepting their repentance by enabling them to repent. And Allah is Forgiving to one who repents for his sins and Merciful to him.