The book was first presented as a paper by the author titled 'The Unity of Asiatic thought' at Banaras in 1930.It grew into a larger volume with each edition and has now reached this massive proportion. The book is almost a textbook on all religions, there are quotations from Sanskrit, Arabic, and Persian languages. Hinduism (including Buddhism and Jainism), Christianity and Islam have been thoroughly studied and projected in an unbiased manner in this book.The book is divided into seven chapters each dealing with specific topics. Religious science and scientific religion, knowledge, devotion, and peace have been discussed. Comparisons and contrasts between the languages, practical examples and explanations of the three main religions of the world have been discussed and explained.