And when we see a Muslim renounce Islam despite retaining the reason by which he was a believer before his apostasy, we know that he acquired that knowledge through something else. Likewise, we see a believer in Allah lose his reason and be judged insane, while retaining his knowledge, affirming Allah’s oneness, and knowing Him. Many rational people disbelieve in Allah and associate partners with Him. This shows that knowledge is acquired through something other than reason.”

This argument implies that the innate faculty and its necessary consequences do not, by themselves, entail the knowledge required of Allah’s servants. No one disputes this. Those who say that knowledge is attained through reason maintain that the basic acknowledgment of the Creator is attained through rational knowledge. Yet this does not constitute all the knowledge one is required to possess, nor does it alone make a person a believer. Reason in this sense is the prerequisite for being subject to commands and prohibitions.

Reason may also refer to that through which salvation is attained. Thus, Allah Most High says of the people of Hell:

“They will say, ‘If only we had listened or reasoned, we would not be among the companions of the Blaze.’”

Allah Most High also says:

“Or do you think that most of them hear or reason? They are only like cattle—indeed, they are even further astray from the path.”

Allah Most High also says:

“Indeed, We have sent it down as an Arabic Quran so that you may understand.”

And He says:

“These are the examples We set forth for people, but none understand them except those who have knowledge.”

There are similar passages in the Quran.

They also cited His words as evidence that knowledge is not attained through reason alone:

“And We gave them hearing, sight, and hearts, yet their hearing did not avail them, nor did their sight