Wahab Ibn Abdullah Al-Sawa’i, who belonged to the generation after the companions of the Prophet, once asked Ali Ibn Abi Talib whether he possessed any divine inspiration which was not contained in the Quran. Ali swore an oath by the One who split the seed and brought life into existence, that they had nothing besides the Quran, “The only additional source of inspiration was the true understanding of the Quran which God bestows upon a person.” (Tafseer Ibn Kathir, Vol. II. p 77).
Ali’s answer shows that it is one thing to understand the written words of the Quran, and another to penetrate into the deep meanings of the Book of God. To understand the words of the Quran all one has to do is read it. But true understanding of Quranic meanings can only come from deep thought and contemplation. The Quran, an ocean of profound meanings; only one who plunges into the depths of its waters can fathom the treasures it contains.