Perhaps the most-well known and accepted of the scholars and saints, is Imam Ghazali. Born in 1058AD in Tus (in modern day Iran), he is known as ‘Hujjah tul-Islam’ (The Proof of Islam). He was a pioneer in the field of spirituality and Sufism. He was amongst the first to consolidate the exoteric and esoteric realities of Islam.

He explained in great depth the concepts and realities of light in his book ‘Mishkat ul-Anwar’ (The Niche of Lights). He discusses how the intellect is like light as its intrinsic function is to unveil. Whatever the intellect is applied to, is unveiled and its nature, realities and qualities are known. The same function exists with light, as whatever is covered in light is then able to be seen and its nature, realities, qualities and much more can be perceived due to the light. This is with outward light. As for inward light, Imam Ghazali says that this reveals the realities of everything. This inward light is only through the light of Allah. Imam Ghazali says:

You should know that just as everything becomes manifest to eyesight through outward light, so also everything becomes manifest to inward insight through God. God is with everything and not separate from it. Then He makes everything manifest. In the same way, light is with all things, and through it they become manifest … It is conceivable that outward light may disappear through the setting of the sun. It becomes veiled so that shadow appears. As for the divine light (Nur) through which everything becomes manifest, its disappearance is inconceivable. Or, rather, it is impossible for it to change, so it remains perpetually with the things.
[Mishkat ul-Anwar (The Niche of Lights)]

The human being has both the outer eye (located in one’s head) and the intellectual faculty – both of which are used to unveil and understand the realities of existence. Imam Ghazali compares the perceptive abilities of the eye and the human rational faculty and states that the eye has 7 imperfections which the intellectual faculty of the human being (i.e. the mind) does not. They are:

1. The eye cannot see itself, whilst the intellect perceives its own attributes and attributes of other things.
2. The eye cannot see what is extremely far from it and what is close to it, while near and far are equal to the intellect.
3. The eye does not perceive what lies behind veils, whilst the intellect moves freely around the veils of the world, the heavens and the earth. It also moves around freely and inside its own self, whereas the eye cannot do this.
4. The eye perceives only the manifest, external dimensions and surfaces of things, not their hidden, internal dimensions and qualities. Or, the eye only perceives their frames and forms and not their realities, whereas the intellect penetrates the hidden dimensions and unveils the mysteries of things, perceiving their realities and spirits. It is able to understand how a thing was created, what it was created from, the meanings of its existence and its relationship with its Creator; such things cannot be perceived with the outer eye alone.
5. The eye primarily only functions with one of the senses, which is sight, whilst the intellect functions using all five senses and more.
6. The eye can only see the temporary and contingent since it can only see the attributes of worldly, manifest bodies, which can only be conceived as finite. The intellect however, is capable of perceiving the infinite.
7. The eye sees large things as small, whereas the intellect perceives things in their true size.

He further discusses how the eye is two eyes: the outward eye and the inward eye. The outward eye is from the world of sensation and witnessing, whilst the inward eye is from the World of Dominion (عالَم الملكوت). He says that every eye has a sun and a light. The outward has a sun which is outward, and that is the sun of our solar system and the inward eye has a sun, which is the Qur’an and the revealed Books of God.

Regarding the Qur’an being light, Imam Ghazali states the following:

“The greatest wisdom is the Speech of God Almighty. From all the Speech of God is the Qur’an, specifically. The position of the verses of the Qur’an according to the eye is the position of the sun according to the apparent eyes, since seeing occurs through it. Hence, it is appropriate for the Qur’an to be called ‘Light’ just how the light of the sun is named ‘Light’. The example of the Qur’an is like the sun and the example of the intellect is like the light of the eye. From this, we understand the sayings of Allah:

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“فَآمِنُوْا بِاللهِ وَرَسُوْلِهٖ وَالنُّوْرِ الَّذِيْ أَنْزَلْنَا”
“Thus, believe in Allah, His Messenger and the light which We have revealed.”

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“قَدْ جَاءَكُمْ بُرْهَانٌ مِّنْ رَّبِكُمْ وَأَنْزَلْنَا إِلَيْكُمْ نُوْرًا مُّبِيْنًا”
“A proof has come to you from your Lord, and We have sent down to a clear light.”

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