Many of the verses are connected with events and circumstances which took place as the Prophet called the people to Islam, for example "The Cow". Other chapters, like "The Tribe", refer to the exile of the Banu al-Nadir and the chapter "The Coursers" was revealed for the bedouin Arabs of the Dry Valley and other tribes. Some chapters or verses were revealed because of the need to explain the laws and directions of Islam; for example, the chapter "Women" which defined marriage and the inheritance of women, "The Spirits" which explains how to deal with the prisoners-of-war captured as booty and, the chapter "Divorce" which was revealed, as its name suggests, to explain divorce. The circumstances leading to the revelation of these chapters are called "reasons for revelation" and there are countless traditions on this subject.

Amongst the Sunni's there are many traditions which deal with the reasons for revelation; several thousand narrations may be enumerated (although in the Shi'ah School only a few hundred may be counted). Many of these are without a chain of narration and are not accepted as fully trustworthy; moreover, a considerable number are classified as weak. The dubious nature of the majority of these may be ascribed to the following reasons. Firstly, it is obvious from the form of many of these sayings that the narrator had not learned them through oral transmission but rather based on his own judgement, that the revelation of a certain verse was connected with certain events. Thus the narrator links a certain event to a verse of suitable meaning mentioned in the tradition. This is a subjective view, carried out through ijtihad or personal reflection upon the matter, and not the actual reason for revelation learned orally through transmission from the Prophet. As proof of this argument, we may cite many inconsistencies amongst these traditions. There are verses, for example, recorded as having several conflicting "reasons for revelation" which are totally unconnected with each other. Ibn 'Abbas, for example, who is not alone in this practice, relates several "reasons for the revelation"' of one single verse. The existence of such conflicting reasons is because many have been arrived at through subjective deliberation rather than transmitted directly from the Prophet. This results in one narrator attributing a certain verse to a particular event while another narrator attributes it to another event.

On other occasions a narrator relates two different reasons for the revelation of one verse and thus implicates himself in two conflicting views; Then he rejects the first view in favour of the second. We are led to conclude, moreover, that most of these narrations are fabrications or deceitfully transmitted under the pretence of trustworthy narrators. Such doubt concerning the validity of many of these traditions greatly endangers their credibility. Secondly, it has been related with certainty that the early Caliphs strictly prohibited the recording and writing down of the narrations and, whenever a sheet of paper or tablet was found on which a saying had been written, it was burned. This prohibition lasted until nearly the end of the first century after Hijrah, that is, for a period of about ninety years. The effect of this prohibition was that the narrators and scholars of sayings were free to make small additions or changes during oral transmission of the saying. These additions gradually accumulated until the original meaning of the saying was lost.

This becomes very clear on investigation of an event or subject which has been related by two different narrators; one may come across a saying which describes an event and see the same event described in a different way by another narrator. False sayings were not only introduced by attributing them to respected narrators but also by the hypocrites. Their sayings soon became part of the main body of sayings and this further undermined the credibility of this particular section of the Science of tradition.