This is to explain the gleam of miraculousness in the repetitions or reiterations of the Qur'an. In this gleam there are six points:

First point

Know that since the Qur'an is a book of invocation, prayer and invitation, its reiteration is very good and in conformity with eloquence; indeed, it is a necessity. For invocation, prayer and invitation are enhanced and strengthened through repetition. Repetition of invocation brings spiritual enlightenment; reiteration of prayer brings satisfaction and peace; and invitation is strengthened through repetition.

Second point

Know that the Qur'an is a [Divine] address to, and a cure for [the "diseases" of] all classes of mankind. It addresses people from the most to the least intelligent, from the most God-fearing to the most sinful, and from the hard-working and those who show success in life or those who have renounced the world, to the miserable and abased and those engrossed in their work. For this reason, it is not always possible for everyone to recite the Qur'an from beginning to end, which is a cure for everybody at all times. So, in order to make it easy, the All-Wise and All-Compassionate One included most of the purposes of the Qur'an in most of its chapters, not only in the long ones, but also in the short ones. It encourages people, declaring, In truth We have made the Qur'an easy for remembrance and warning. Is there any that will remember and take warning?¹⁶

Third point

Bodily needs vary. Some of them like air are constantly needed. Others like water are needed on occasion of thirst or in response to heat. Some like food are needed everyday, others every month or every year or, those like medicine, on irregular occasions only. So too, man's spiritual needs vary. While some of the Qur'anic words and verses like He and Cod are constantly needed, among others there are those like In the Name of God that are usually needed, and those needed very frequently like There is no god but God.

So, the repetition of certain verses and words is because of the recurrence and intensity of the need for them. Again, in order to remind of the need for them and urge people to feel the need for certain "spiritual sustenance," certain verses and words are repeated in the Qur'an.

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16. al-Qamar, 54.17.