For each (such person) there are (angels) in succession, before and behind him: They guard him by command of Allah. Allah does not change a people's lot unless they change what is in their hearts. But when (once) Allah willeth a people's punishment, there can be no turning it back, nor will they find, besides Him, any to protect. (11)
Tafsir
The rise and fall of the communities of the world do not happen at random, but rather under the care of and by the decision of God. When God blesses a community with His bounties, He continues this blessing so long as that community keeps its competency intact. After losing this competency, that community necessarily loses God’s grace also, for example, after losing internal unity, its impact on the world, is lessened. Whatever a community achieves in this world, it achieves by the law of God and whatever a community loses, it loses it by the law of God. There is nobody here who is capable of giving or capable of taking away except God.
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