the opposite positioning is not produced by any one created being, nor is the motion, then no one created being is the agent of the resulting effect. This is the correct and certain conclusion: no generated effect can be the act of a single created agent. Rather, each of the two things is a cause of it, and both share and cooperate in producing it. We have explained that no created being performs a complete act without another’s participation. The Creator, glorified be He, is the One besides whom there is no deity, alone, without partner. His is the dominion and His is all praise, and He has power over all things.
This becomes clear upon examining the example they mentioned. When someone taps a basin and a sound arises, that sound necessarily depends both on the person’s action and on the body that receives the tap. Every sound a person produces outside himself therefore requires another body besides his own. As for the sound arising within his own body, he moves two or more of his organs: sound does not arise through the movement of just one thing. The two movements together are thus the cause of the sound.
Although he is the one who moves his organs, the organs themselves, the cavity within them, and the hardness that enables them to produce sound are neither his own work nor within his power. Rather, Allah created these for him and made them his instruments, just like instruments separate from his body. His own power, therefore, cannot independently produce sound without these things that lie beyond his power.