A Muslim should therefore beware of these two pernicious principles and what they engender among some Muslims: disparaging and cursing other Muslims, and deeming their blood and property lawful. These two principles run counter to the Sunnah and the Muslim community. Whoever opposes what the Sunnah has brought or prescribed is an innovator who has departed from the Sunnah. Whoever declares Muslims disbelievers because of something he considers sinful—whether it is actually part of the religion or not—and treats them as disbelievers has separated himself from the Muslim community. Most innovations and deviant inclinations arise from these two principles.

The first involves specious reasoning based on faulty interpretation or faulty analogy. A person may receive an inauthentic hadith attributed to the Messenger, or a report from someone other than the Messenger whom he follows in that matter, although that person was mistaken. Alternatively, he may incorrectly interpret a verse from Allah’s Book, a hadith attributed to Allah’s Messenger, may Allah bless him and grant him peace—whether authentic or weak—or a transmitted report, whether accepted or rejected. Or he may employ a faulty analogy, or form an opinion that he believes to be correct when it is mistaken.

Analogical reasoning, personal opinion, and spiritual intuition account for most of the errors of speculative theologians, Sufis, and a group of those engaged in jurisprudence. Faulty interpretation of authentic or weak texts accounts for most of the errors of various groups of speculative theologians, hadith scholars, uncritical followers, Sufis, and those engaged in jurisprudence.