12th century, Tibet
A text by Gampopa (1079-1153), a student of Milarepa and later one of the essential teachers for the development of the Kagyudpa lineage.
In this work, Gampopa unified several theories, concepts and teachings that were becoming separated in the various schools arising during this early period of Tibetan Tantric Buddhism.
Mainly, he combined the Mahamudra teachings of
Milarepa and the Naro Chosdrug of
Naropa into a new synthesis.
Having been first educated, in his youth, by the
Kadampa, he also assimilated elements of this more
monastic strand of teachings into his work.
Guenther, H.V. (trans.) The Jewel Ornament of Liberation by sGam.Po.Pa. London: Rider, 1959. Boston and London: Shambhala, 1971.