The point here is to draw the Muslim’s attention to the fact that, however thoroughly sound reason is examined, it can only agree with the revealed law brought by the messengers. Thus, the truth of its teachings becomes clear to you through rational proofs that require no informant’s testimony, even if that informant is infallible. Rather, scriptural and rational proofs—those based on reports and those based on reasoned inquiry—reinforce one another.

As Allah Most High says:

“We will show them Our signs in the horizons and within themselves until it becomes clear to them that it is the truth. Is it not sufficient that your Lord is a witness over all things?”
[Fussilat: 53]

People differ in this, however, according to what Allah grants them of reason, knowledge, reflection, the ability to draw inferences, and discernment. The more fully someone recognizes what is correct in these matters, the more fully he recognizes this agreement and correspondence.

Those who have experienced this can attest to it. Before becoming certain of what the Sunnah teaches, a man may harbor doubts and misconceptions, supposing that it has been contradicted by the objections raised against it—whether drawn from rational arguments, experiential judgments, or policies of governance. Then, when Allah guides him and directs him aright, it ultimately becomes clear to him that what accords with revealed law is precisely what sound reason dictates, what sound experiential judgment recognizes, and what perfect governance requires. Whatever contradicts this belongs to the ways of the ignorant and unjust.

Allah speaks the truth and guides to the way:

“And He guides whom He wills to a straight path.”
[Yūnus: 25]

[The Tenth Argument]

There is no statement that accords with the Sunnah for which the people of reason who affirm it are not more numerous and more distinguished than those who deny it. Indeed, you find those who agree with it