Because the Qur’an is the word of God, the words cannot be changed. Like contemporary speakers of English trying to read Old English, “modern Arabic speakers cannot read the Qur’an and understand it,” wrote Ali-Karamali, “because it’s so old.
“Meanings of words have changed,” she explained, leaving much argument as to what should be read literally and what should not.
“Islam rejects the ‘orthodox vs. non-orthodox’ theory of religion,” writes Ali-Karamali in her book.
There is no central authority. Ali-Karamali names five major schools of thought — all considered valid — that have produced guidelines of Islam based on their interpretations of the Qur’an and Sunnah, the way the Prophet Muhammad lived his life.