Chapter 38 of the Quran has this to say: “This is a blessed Book which We sent down to you [Muhammad], for people to ponder over its messages, and for those with understanding to take heed.” (38:29) From this verse we learn that the Quran is not meant merely for verbal recitation: it is for the reader to make use of his mind and reflect upon and ponder over its verses in order to learn the lessons hidden in the verses or between the lines.
There are many traditions of the Prophet as regards the importance of the mind. The wording of one of these is: “Everything has a pillar and the pillar of a believer is his reason or mind (aql).” (Musad al-Haarith, Hadith No. 840)
There is another hadith of relevance in which the Prophet of Islam observed: “Every verse of the Quran has an external aspect or form and an internal essence or inner aspect.” (Musnad Abu Yala, Hadith No. 5149)
The apparent meaning of the verses is understood by just reading the verses, but the deeper meaning can be arrived at only by employing reason, and pondering upon what one reads. The reader, thus, reaches the deeper level of the meaning of the verses by reflection. This deeper realization of the Quran produces sublime feelings of faith in one. While without making use of reason, one arrives at a form of religion which is superficial. It is only by making use of reason that the seeker can find the true kernel of religion.
Source: God Oriented Life