The same applies to statements whose utterance constitutes unbelief. A person may not have received the scriptural texts that would make the truth known to him; or he may have received them without their authenticity having been established to his satisfaction, or without being able to understand them. He may also have encountered doubts for which Allah excuses him. Any believer who strives diligently to seek the truth but errs will have his error forgiven by Allah, whatever it may be, whether in theoretical or practical matters. This is the position of the Prophet’s Companions—may Allah bless him and grant him peace—and the great majority of the imams of Islam. They did not divide questions into fundamental matters whose denial constitutes unbelief and subsidiary matters whose denial does not.

As for distinguishing between one category called fundamental matters and another called subsidiary matters, this distinction has no basis in the teachings of the Companions, those who followed them in righteousness, or the imams of Islam. Rather, it derives from the Muʿtazilah and similar adherents of religious innovation. It was from them that the jurists who mentioned it in their books acquired it. Moreover, this distinction is inconsistent, for anyone who distinguishes between the two categories is asked:

What defines the fundamental matters in which a person’s error constitutes unbelief? What distinguishes them from subsidiary matters?

If he says that fundamental matters concern belief, whereas subsidiary matters concern practice, he is told in response:

People have disagreed over whether Muhammad—may Allah bless him and grant him peace—saw his Lord; whether ʿUthmān was superior to ʿAlī or ʿAlī was superior; and over many meanings of the Quran and the authenticity of certain hadiths. These are matters of belief and knowledge, yet there is agreement that error in them does not constitute unbelief.