One of the important issues in enjoying Quranic verses, is the fact that which instruments can be used to understand Quran better and which obstacles should be removed to achieve this goal without any mistakes.Imam Khomeini and Professor Tabatabaee who are among the greatest thinkers and philosophers of Shi’a world believed that comprehension of Quran has outstanding significance .Thus, in this study, aiming at defining instruments and obstacles of comprehension of Quran , the viewpoints of the mentioned remarkable thinkers were discussed and finally the research led to the point that both Quran interpreters attempted to define related effective tools and indicated the obstacles on the way. The mentioned tools instruments can be categorized into two groups:Intercontextual and out_of_ context: some of the most important tools are as follows: paying attention to Arabic syntax and morphology compotability of verses, conceptual and structural coherence (regarding similar and definite verses),unique goal of the whole Surah. Enjoying virtue and inner purification, reflection and meditation in Quran, attention to interpretations and acquaintance with holy Quran
