You also maintain that He necessarily produces His effect by His very essence and is a beginningless, complete cause whose beginningless effect coexists with it and does not come after it. Yet it is well known that differing temporal events proceeding from a beginningless, simple, complete cause—whose necessary consequence and effect can never fail to accompany it—is even more clearly impossible than temporal events proceeding from an agent endowed with power and choice after they had not previously proceeded from Him. If temporal events cannot arise from a beginningless being in whom no temporal event subsists, your position is even more clearly impossible. If they can, then the Mu'tazilites’ position is more tenable.
For if their position entails that temporal events have no newly arising cause, your position entails that temporal events have no originator whatsoever. Yet temporal events are observable, and their originator must exist when they exist. Everything required to bring them into being must also be present when they are brought into being. This, however, cannot proceed from a complete cause.
It thus becomes clear that the very premises with which the philosophers argued against the Mu'tazilites and their followers for the beginninglessness of the world can be used to argue that the world came into being. Their proof rests on the claim that a beginningless, complete cause necessarily entails its effect: if the Creator were not a beginningless, complete cause, things would necessarily come into being without a cause; if He were a beginningless, complete cause, His effect would necessarily coexist with Him. Thus, they conclude, the world must be beginningless.
But His being a complete cause is impossible, because the entire effect of a beginningless, complete cause coexists with it; no part of its effect comes after it. The world, however, is inseparable from temporal events that accompany it, as is necessarily evident and agreed upon by the vast majority of rational people. Whatever necessarily entails temporal events cannot be the effect of a beginningless, complete cause, since it is impossible for temporal events to arise