For this reason, you find that faith does not become firmly established in the heart of someone accustomed to opposing revealed teachings with personal opinion. Rather, his condition is as the imams described:

“The scholars of speculative theology are heretics.”

They also said:

“Rarely does anyone study speculative theology without harboring resentment toward Muslims.”

By practitioners of speculative theology, they meant those who speak about Allah in ways that contradict the Quran and Sunnah.

In short, a person cannot be a believer until he believes in the Messenger with firm conviction, unconditionally—not merely in the absence of contrary evidence. Whenever he says, “I believe what he reports unless contrary evidence emerges that refutes it,” he does not truly believe in him. This is a fundamental principle that must be understood, for such a statement opens the way to irreligion and hypocrisy.

[The Fourth]

Fourth: They have conceded that certain matters are known through transmitted revelation. They all state that knowledge falls into three categories: what is known only through reason, what is known only through transmitted revelation, and what is known through both transmitted revelation and reason.

This division is broadly correct. Some matters beyond human sensory perception cannot be known through reason; they can only be known through reports.

There are three means of acquiring knowledge: sense perception, reason, and a combination of the two, such as reports.

Some matters can therefore be known only through reports, as everyone knows from the reports of truthful people, such as mass-transmitted reports, and from what is learned through the reports of the prophets—may Allah bless them all.

This division must be acknowledged. Conclusive proofs have established the prophethood of the prophets, and that they may learn through reports what can only be known through reports. Likewise, they impart knowledge to others through their reports.