The Treasury of Precious Instructions, compiled by Jamgön Kongtrul Lodrö Taye, one of Tibet's greatest Buddhist masters, is a shining jewel of Tibetan literature, presenting essential teachings from the entire spectrum of practice lineages that existed in Tibet. In its eighteen volumes, Kongtrul brings together some of the most important texts on key topics of Buddhist thought and practice as well as authoring significant new sections of his own.

Teachings and practices of the Nyingma lineage, the first of the eight lineages, are presented in the first and second volumes of the series, the second one of which is translated here. These texts are all related to the three yogas: Mahāyoga, Anuyoga, and Atiyoga. The first Nyingma volume includes works that are representative of the first two yogas, while this volume focuses especially on those belonging to the "pith-instruction class," specifically those related to the unsurpassed secret section--the Heart Essence, or Nyingtik. According to the understanding of the Nyingma school, the most profound tenet of the Buddha's teachings is that within the mind of every being--as its bedrock, fundamental stratum, or element--lies the buddha nature. The teachings of this volume each present this essential tenet in a variety of ways and are composed by various Tibetan and Indian masters, including the Buddha, Garab Dorje, Mañjuśrīmitra, Śrīsiṃha, Jñānasūtra, Padmasambhava, Longchen Rabjam, and Jamgon Kongtrul Lodrö Taye.