Anyone who prays the five daily prayers would have to admit this, because not only are the words for the prayers not given in the Quran, even the number of daily prayers is not mentioned. The Quran mentions only three daily prayers, and it does not delineate the words or postures for any of them. Although there are legitimate “Quran-only” Muslims, they have always been an extreme minority in Islam. Most Muslims who argue against the law of apostasy using a Quran-only approach are using reasoning that would radically alter their Islamic practice if applied consistently.
