Vijnanabhairava is a very ancient book on yoga. It closely follows the basic principles of Saivagama. It studiously eschews mechanical worship, external rites and ceremonies and goes directly to the heart of the problem of the union of human consciousness with the Divine.
Excellent and readable translation of the (Kashmir Shaivism) Vijnana Bhairava Tantra, with Sanskrit, transliteration and interpretation by the author. Since there aren't many translations around, this gives new light to some of the existing (and less accurate) translations. The tantra itself is highly practical and minimalist in instructions, hence it is an excellent source for those on the path of spiritual practice (or those interested in experimenting with methods).
I consider this tantra to be a guide to life and happiness, and this translation is wonderful. Jaideva Singh is a direct disciple of Swami Lakshmanjoo, and his commentary is invaluable. An excellent source of information for intermediate and advanced meditation practitioners.
A companion for more than 30 years the VBhT still offers me inner peace and Wisdom. The English translation is not great but if read slowly and with some basic Sanskrit knowledge the reading is perfect. The most important thing on reading this book is to practice. Verse 24 still offers the experience of the whole book if practicing purposely. Hamsa has been and still is my greatest companion. Swami Muktananda wrote a book on this verse and although his elucidation is quite good and helps at entry level his philosophical approach to the text is not consistent with the tradition of Abhinavagupta, for which I recommend to read Swami Lakshman Jee commentaries.