In Islam, the branch of Qur’an Sciences is known as Tafseer. This refers to the practice of explaining and elaborating on the Qur’an.
This is done because much of the Qur’an is difficult to access and fully comprehend if one is not trained in classical Arabic grammar or in the usage of Classical Arabic, in addition to a number of other disciplines.
It is also because the inner and hidden meanings of the Qur’an can only be accessed and understood by people chosen by Allah (s.w.t). Tafseer works generally comprise of works which gather clear cut statements from the Prophet (s.a.w) and the Imams (a.s) in which they reveal some of the aspects of the Qur’an that people would not necessarily be able to understand.
There are different styles of Tafseer, such as relying on narrations from the Prophet (s.a.w) and Imams (a.s), or on the Qur’an itself to explain one verse with another.
Other Tafseer such as that of Shaykh al-Tusi are more focused on comparative Tafseer, mixing discussions of Hadith as well as grammar. Some books of Tafseer are entirely based upon themes and so do not actually discuss the entire Qur’an.
These Tafseer are concerned with discussions relating to beliefs as well as different rules from Islamic Law which can be derived from the Qur’an.