This book is an abridged English rendition of the latter part of Āyatullāh Muḥammad Hādī Ma‘rifat’s magnum opus, Al-Tamhīd fī ‘Ulūm al-Qur’ān (Introduction to the Sciences of the Qur’an) which can be considered a significant contemporary contribution to ‘Ulūm al-Qur’ān.
‘Ulūm al-Qur’ān is a branch of science which deals with such subjects as revelation and the sending down of the Qur’an, the duration and order of revelation, circumstances surrounding the revelation, the collection and recording of the Qur’an, scribers of the revelation, standardization of the manuscripts, the emergence of different readings (qirā’āt) and the origin of differences in Qur’an reading, the Qur’an’s authority and immunity from distortion (taḥrīf), the issue of abrogation (naskh) in the Qur’an, the emergence of its allegorical verses, the Qur’an’s inimitability (i‘jāz), etc. And since each of these issues has its own framework and is considered distinct from each other, this science is in plural form (‘ulūm which literally means ‘sciences’).
In this book, after initially identifying different factors that contributed to the emergence of the notion of taḥrīf or textual distortion of a scripture, the author discusses in length the textual and technical meanings of taḥrīf – including the notion of abrogation of recitation and the issue of insā’ (being forgotten). He then gives a summary of the proofs of invalidity of the notion of taḥrīf. In the succeeding two chapters, he enumerates and gives examples of alleged taḥrīf according to the Hashwiyyah and Akhbārī schools of thought.