know." [Q 12:21]
Let us illustrate this with an example. A man sets out for ʿumrah, but along the way his car breaks down. He turns back and says, “If only I had taken the other car, things would have been better and I would not have been stranded.” We reply, “Do not talk like that. You already exerted the effort, and had Allah willed that you reach ʿumrah He would have made the matter easy for you. Allah simply did not will it.”
Therefore, when a person has done what he is able and what he has been commanded to do, yet events still turn against him, he must entrust the affair to Allah, for he has done all that lay within his power. Hence the Prophet said, “If something befalls you”—that is, after you have exerted effort and sought Allah’s help—“then do not say, ‘Had I done such-and-such, it would have been this or that.’”
May Allah reward our Prophet on our behalf with the best reward, for he explained the wisdom behind this when he said, “For ‘if only’ opens the door to the work of Satan.” It opens for you the gates of whisperings, sorrow, regret, and anxiety until you keep saying, “If only I had done so-and-so, it would have been this way.” Do not speak like that—the matter is finished and can never be altered. It was written in the Preserved Tablet fifty thousand years before the heavens and the earth were created, and it will remain exactly as it is, no matter what you do.
For that reason he said, “Instead, say: ‘It is Allah’s decree.’” Meaning: this is Allah’s pre-ordainment and judgment, and whatever Allah wills, He does—“Indeed, your Lord is Doer of whatever He wills” [Q 11:107]. No one can prevent Him from carrying out in His dominion whatever He wishes; whatever He wills, He does.
Yet we must also know that He does nothing except for a wisdom—whether hidden from us or apparent to us. The evidence for this is His statement: “And you do not will except…"