imam ali (a.s.), the second quranic interpreter cognizant of all quranic depths

quranic knowledge and injunctions can be explained and understood in three levels, and its full grasp will not be possible without considering the prophet¨s interpretation of the qur'an. it is necessary for an interpreter of the qur'an to have access to the prophet¨s interpretation. that is why imam ali, the rightful successor of the prophet, is regarded as the second interpreter or, strictly speaking, an exegete of the qur¨an in all its exoteric and esoteric aspects. particular and general traditions show that imam ali (a.s.) was fully informed by the prophet of the knowledge of revelation and its esoteric meaning. some quranic verses and traditions, whether general or particular, reveal that imam ali was completely cognizant of the quranic wisdom and injunctions. being based on quranic verses and certain traditions, this article deals with imam ali's knowledge of the quranic exegesis, his authority on quranic knowledge and quranic injunctions and his exegetical works, especially his sermons, letters, and orders which were compiled and organized by sayyed al-rad¤i and named ``nagj, al-balaghah'' (with a glance at the scholars' assertions on the subject in question).