The Revival of the Religious Sciences by Imam al-Ghazali can be described as a book that will never die. This is because it contains a vital cognitive force that time cannot obliterate. In it the Imam discusses Islamic rulings, beliefs and character, in the style of an admonisher who understands the psyche and its secrets as well as spiritual diseases. What distinguishes this book from others is its strong spiritual influence on the reader which makes him seek both soundness of heart and his Lord's pleasure through acts of worship, rather than the mere performance of acts of worship so that they are legally valid.
The book is a comprehensive encyclopaedia for all of a Muslim's religious affairs, including beliefs, acts of worship, dealings and character, as well as for individual and societal welfare. Al-Ghazali's style is that of one who practices what he knows, one who is determined to rise from the dry, ordinary manner of teaching to one which encourages action.
Abu Hamid al-Ghazali is a towering figure in Islam. His enormous influence can be summarized, in the words of Annemarie Schimmel, as the one who "teaches... only to help man to live a life in accordance with the sacred law, not by clinging exclusively to its letter, but by an understanding of its deeper meaning ... so that he is ready for the meeting with his Lord at any moment." His greatest work Ihya' 'Ulum al-Din (The Revival of the Religious Sciences), comprising forty books divided into four quarters of ten books each, has helped generations towards this end until today.