The majority of the miracles of the prophets were in the realm of the senses, and confined to their own times and only their contemporaries witnessed them. The miracle of the Qur’an, however, abides until the day of resurrection. The miracle is its transcending the natural in style and eloquence and in its revelation of the hidden mysteries. There will never come an age in which something of its message will not be manifest. It will continue to give evidence of the authenticity of its claims.” In other words the physical Qur’an is the material crystallization of the infinite reality of Quran 
The Qur’an is like the universe with many planes of existence and levels of meaning…. It is essential to realize that we cannot reach the inner meaning of the Qur’an until by the grace of God, we ourselves have perpetrated into the deeper dimensions of our being. If we approach the Qur’an superficially and are ourselves superficial beings floating on the surface of our existence and unaware of our profound origin, then the Qur’an appears to us as having only a surface meaning. It hides its mysteries from us and we are not able to penetrate it. It is by spiritual travail that man is able to penetrate into the hidden meaning of the sacred text
Jalal-al-Din Rumi, poet of Persian mysticism, describes the believer’s relation to the Qur’an as follows:” Some men are infants of the way and take pleasure in the literal meaning of the Qur’an drink that milk. But those who have reached years of full discretion have another enjoyment and different understanding of the inner meaning of the Qur’an.
The student of the Qur’an has to distinguish between the inner and outer, the esoteric and the exoteric, aspects of the teachings
Rumi, in Masnavi, expressed the hidden mysteries of Qur’an as follows:
Know the words of the Qur’an are simple,
But within the outward sense is an inner secret one.
Beneath the secret meaning is third
Whereat the highest wisdom is dumfounded
The fourth meaning has been seen by none
Save God, the Incomparable, the All Sufficient.
Thus they go on, even to seven meanings, one by one,
According to the saying of the prophet without doubt:
Do thou, O son, confine not thy view to the outward meaning
Even as the demons saw in Adam only clay.
The outward meaning is like Adam’s body:
For its semblance is visible but its soul is hidden
- Kenneth Cragg and R. Marston Speight, Islam from Within: anthology of a Religion, Wadsworth Publishing Company, 1980, p.18