The Dharma Patanjala is an Old Javanese-Sanskrit Saiva text that was translated into English and studied in this book. It was transmitted through a single palm-leaf codex of West Javanese origin that dates back to the 15th century AD.

Part I introduces the text's codicological and philological features as well as its cultural and ideological context. A critical edition with an English annotated translation follows the annotated diplomatic edition of the text in Part II, which also includes facsimile copies of the codex on facing pages. Part III is a systematic study that focuses on how the Dharma Patanjala's ideas should be interpreted in light of relevant Sanskrit writings from the Indian subcontinent and Old Javanese texts from the Indonesian Archipelago.

Instead of the Saiva sadangayoga that is common in other Old Javanese works, the author of the Dharma Patanjala embraced a version of Patanjala astangayoga and adjusted it to a Saiva doctrinal framework. When developing his hybrid system, the author adhered to a commentarial tradition to the Sanskrit Yogasutras that is similar to the Yogasutrabhasya but distinct from it. The Vrhaspatitattva and the Tattvajnana are the only two Old Javanese scriptures that provide us with information about an early tradition of speculative literature (Tattva), which is also documented in the Dharma Patanjala. This significant literature thus closes a knowledge gap about Saiva philosophy and theology in pre-Islamic Indonesia and sheds light on Saivism's emergence and growth in the Indian Subcontinent.