O Prophet! say to those who are captives in your hands: 'If Allah findeth any good in your hearts, He will Give you something better than what has been taken from you, and He will Forgive you: for Allah is Oft-Forgiving, Most Merciful. But if they have treacherous designs against thee, (O Messenger!), they have already been in treason against Allah, and so hath He given (thee) power over them. And Allah is He who hath (Full) knowledge and wisdom. (The Noble Quran, 8:70-71)"
The following explanation of Noble Verses 8:70-71 was taken from the commentary of Sheikh (Minister) Abdullah Yusuf Ali's (may Allah Almighty rest his soul) English translation:
"This is a consolation to the prisoners of war. In spite of their previous hostility, Allah will forgive them in His mercy if there was any good in their hearts, and confer upon them a far higher gift than anything they have ever lost. This gift in its highest sense would be the blessing of Islam, but even in a material sense, there was great good fortune awaiting them, e.g., in the case of Al-Abbas (who was among the unbelievers and was taken as a prisoner of war).
Note how comprehensive is Allah's care. He encourages and strengthens the Muslims, at the same time condemning any baser motives that may have entered their minds. He consoles the prisoners of war and promises them better things if there is any good in them at all. And He offers comfort to those who have left their homes in His Cause, and knits them into closer fellowship with those who have helped them and sympathized with them.
If the kindness shown to them is abused by the prisoners of war when they are released, it is not a matter of discouragement to those who showed the kindness. Such persons have in their treachery shown already their treason to Allah, in that they took up arms against Allah's Prophet, and sought to blot out the pure worship of Allah. The punishment of defeat, which opened the eyes of some of their comrades, evidently did not open their eyes. But Allah knows all, and in His wisdom will order all things for the best. The Believers have done their duty in showing such clemency as they could in the circumstances of war. For them "Allah sufficeth" (Noble Verse 8:62)" [2].