"Füqhu'l-evleviiât" (principles) is a term bound by Islamic law, which consists of complementing the words "fuqh" and "evleviyyat". Meaning "priority issues", the term "priority" refers to the term "fikh" meaning "the theoretical principles that help oneself in cases where a person is in contradiction in the opposite of the judgments or in which he or she should prioritize when he is living in these provisions". This study has tried to process the sources, evidence and some rules of the Nass.