Question: Why are some ayats repeated in the Qur’an and in this way why are some stories mentioned on many places?

Answer: We should remember that the Holy Qur’an was revealed over a period of 23 years according to different circumstances and happenings. The Holy Qur’an is not a dry jurisprudence book or a classic that should present an analysis of intellectual problems and laws.
The Holy Qur’an is a discourse, a book of religious propagation and guidance whose aim is enunciate the realities of human life and laws that are necessary to take humanity to perfection and they should purify the souls and thoughts of people and establish the proper social laws so that a society is established which would be perfect from the economic as well as the ethical point of view. To achieve this aim the Holy Qur’an has spoken on all the important subjects. The Holy Qur’an is revealed over a period of 23 years in different circumstances to reply to the needs.
Now so far a repetition is concerned we see that there are two types of repetitions.
1. Repetition of some historical stories.
2. Repetition of those ayats which mention some very special kinds of realities.
As regards the historical incidents we should remember that the aim of Qur’an relating the historical incidents is to invite the attention of the people towards the laws which have ruled over the past communities.
The Holy Qur’an desires to familiarize the people with those laws and invite their attention towards the causes of the advancement and progress or downfall of the past nations. What were the serious consequences of their rejection of their prophets? What they had to suffer as the result of unleashing justice and oppression. What were their actions which cause of their downfall and destruction? And finally what were the signs of their weakness and strength.
In those ayat the Holy Qur’an has invited the attention of the people towards those laws and in this same way indicated the consequence of the disobedience of the sinful and oppressive people.
The same fact became the cause that the Holy Qur’an should analyze the past societies and indicate towards their different aspects.
Therefore the Holy Qur’an mentions for example the Bani Israel and the creation of Adam (a.s.) in different places. On every occasion it indicate towards a special part of loftiness of this incident and desires that every time it should invite the attention of the people to an special aspect which has not been indicated other times.
It is a reality that can be realized only if you ponder upon the stories of the Holy Qur’an. The poets that are repeated on other occasion (for example Surah Rahman the ayat of: which then of the bounties of your Lord will you deny?) is for the purpose to create a psychological effect on the hearers.
When the Almighty desires to exhort people He repeats to them again and again those points which have special psychological and emotional aspect. For example in the same Surah Rahman the Almighty Allah enumerates some important bounties that have fundamental effect on the formation and continuation of human society. And in the same the major bounties are mentioned; that are arranged for man in the hereafter.
The aim of enumerating those bounties is to awaken the emotions of man. Allah repeats the sentence: Which then of the bounties of your Lord will you deny, so that people develop the ability to recognize truth and it prepares him to submit to the truth and develops his humanity and feelings. Therefore the repetition of this type is itself necessary from the point of view of guidance and it does not in any way mar the eloquence of Qur’an, rather it is counted as the beautiful discourse because it first of all becomes the cause of emphasis and effect.
This type of repetition is widely seen in the Urdu, Arabic and Persian literature. And there are numerous examples of Arabic Panegyric (Qasida) which are designed on the repetition of one sentence or stanza. One such example is the Qasida of Adi bin Rabiah the uncle of Imrul Qays, which he composed in the memory of his brother, Kaleeb. The sentence Alaa Laisa Adlam min Qaleeb is repeated twenty times. And of the Urdu poets, especially in Dr Iqbal's poetry we find such examples of repetition.