It is not possible for every Muslim individual to learn the religious issues, decrees and judgments directly from the Quran and Sunnah. Only authorized Islamic scholars that have reached the level of ijtihad can do it. The other Muslims need to understand and adopt the explanations and views of those scholars and follow their way. The raw materials of drugs are plants, herbs, mines, etc but not everybody can produce drugs using them; it is necessary to study pharmaceutics; similarly, an ordinary Muslim cannot make judgments about religious issues although the sources are the Quran and Sunnah; only scholars that have reached the level of ijtihad can make judgments about religious issues. Not everybody can have enough knowledge, mental capacity, reasoning, intelligence and foresight to make judgment from religious sources.