When leadership and religious authority was transferred to Shaykh al-Taifa, the illuminated Shi’a faith was fully introduced to the Muslim world and the strength of the reasonings of its scholars became clear to all. Hence it became the target of much attention from two aspects: from severe opponents as well as supportive researchers. Sometimes questions, doubts, objections and even refutation to Shi’a theology were made, which were not new and scholars replied to them and even after the Shaykh, such objections are completely refuted, but they were especially restricted to the time of the Shaykh [as mentioned in his biography], which finally led to the destructive events against Shi’a. Without any doubt, the most important controversial topic was that of occultation (Ghaybah) of the Master of the Age (aj), against which the opponents expended their most efforts.

The Late Shaykh started writing this book in 447 A.H. as the final refutation of objections aimed against occultation (Ghaybah) and he has mentioned the special features of this book in his introduction. An important point is that the Shaykh wrote this book during a period when he was under tremendous pressure and when opponents were hatching different conspiracies against him. They also attacked his house, library and even his chair of honour and burnt them down in 449 A.H., which compelled him to move to Najaf Ashraf.

However, even during such precarious times, the Shaykh wrote this book in the best style and included in it all important points; some of which are as follows:

1) Evidences of the existence of the Master of the Time (‘a).

2) Refutation of beliefs of Kaisaniya, Nawusiya, Fatiha, Waqifiya, Ismailiya etc., who are out of the pale of the guidance of Ahl al-Bayt (‘a).

3) Evidences of occultation and longevity of Master of the Age (aj).

4) Philosophy and wisdom of occultation (Ghaybah).

5) Accounts of those who have seen the Imam.

6) Manners, morals and academic excellence of Imam al-Mahdi (aj) ...and other issues from true recognition of the Holy Imam (‘a).

Without any doubt, the Book of Occultation by Shaykh Al-Tusi is the most important and comprehensive book on the subject of occultation (Ghaybah) of Imam al-Mahdi (aj) and it shall be useful to the laymen as well as scholars, if Allah wills.