nor between al-Khidr and Moses. For in every case, whether a person acts or refrains, ability concurrent with the act is not present before the act. The Quran indicates that this ability is denied only of the one who refrains, not of the one who acts. Thus, it is understood to be opposed to the impediments within a person that prevent his heart from willing and performing the act. In any event, this ability is absent in someone for whom it has been written that he will not act—indeed, this has been decreed for him.
Once this distinction is understood, it becomes clear that both unrestricted assertions are erroneous and constitute innovation: the assertion that a person cannot do anything other than what he has done, or anything contrary to what Allah knows and has decreed; and the assertion that those who act and those who refrain have the same ability, with no particular ability distinguishing the former from the latter.
For this reason, the early generations of the Muslim community, its leading scholars, and the majority of the schools of speculative theology agreed that Allah has power over what He knows and has declared will not occur, and over that which cannot proceed from Him because He does not will it, not because He lacks the power to do it. Only certain misguided groups among the Jahmiyyah, the Qadariyyah, and the Sabian philosophers disagreed. They claim that what is possible through His power is confined to what actually exists, restricting His power to what He has willed and knows will exist, to the exclusion of what He has declared will not occur. This was the position preferred by al-Nazzām and al-Aswārī. Likewise, some claim that no world other than this one is within His power, and that nothing within His power could guide one who is astray.
Yet Allah, Most High, has said:
“Does man think that We will not gather his bones?
Yes indeed, We are able to make even his fingers level.”
Yet He, glorified be He, does not make his fingers level. And He, Most High, has said:
“Say: He is able to send upon you