"And you see the mountains, thinking them solid"—stationary—"while they pass like the passing of clouds." They will become like wool, teased and scattered, and will become a heap of shifting sand, and they will be ground into dust, just as flour is ground. Then they will become a mirage, then they will become dust dispersed. That is when they are removed from their foundations, and nothing of them is seen; the entire earth will become level, "the work of Allah, who perfected all things."
Muhammad said: The recitation is "sun'a Allah" (the work of Allah) in the accusative case (mansub), in the sense of an infinitive, as if He said: Allah made that as a work.