Innate human nature rejects the notion that two agents enjoy identical ability while only one of them possesses the decisive will even more decisively than it rejects the idea that an effect could be delayed after its cause. What, then, when someone claims that power and will at the very moment the act occurs are exactly as they were beforehand, and that the act took place without any new factor arising at all?
Instinct itself teaches that such a claim is false. It knows that, when an act comes into existence, the causal influence must be complete: the agent must at that point possess a firm, determined will and a fully effective power. Once perfect power and decisive will converge, the intended, possible act must necessarily come to be.
There is no doubt that Allah is All-Powerful over everything, as the Qur’an proclaims in many passages. His power is an essential attribute of His very being, and its scope encompasses whatever is possible; it is not confined to one possible thing rather than another. By unanimous rational agreement, what is impossible in itself is not a “thing” at all, and its existence in external reality is inconceivable. One cannot conceive of something being simultaneously existent and nonexistent, or both moving and motionless, or of the successive parts of motion being present at one instant, or of today co-existing with yesterday and tomorrow, and the like.
Such impossibilities, therefore, do not fall under the Qur’anic declaration of universality. As for what is “impossible” for another reason—that is, whatever Allah knows will not be, has informed us will not be, and has written will not be—these things fail to occur because He has not willed them and has decreed that they shall not be. For “whatever Allah wills comes to pass, and whatever He does not will does not come to pass.” Yet, had He willed any of those matters, He would have brought them to fruition, just as the Qur’an states in several places: “Had Allah willed, He would have guided every soul,” “Had He willed, He would have made all people a single community,” and similar verses.