Nubchen Sangye Yeshe was one of the twenty-five principal students of Guru Padmasambhava, founder of the Nyingma school of Tibetan Buddhism. Nubchen Sangye Yeshe is considered an important figure in the development of the White Sangha of lay yogis.
Nubchen Sangye Yeshe wrote Armor Against Darkness, a major commentary on The Six Tantras Clarifying the Six Limits, the central tantra of the Anuyoga tradition. Namkhai Norbuet al. identifies Nubchen Sangye Yeshe as the author of a treatise, Samten Migdrön. Dalton states that:
Nubchen Sanggyé Yeshé is renowned for having preserved a number of tantric lineages through the so-called “dark period” of Tibetan history, when state-supported monastic Buddhism fell into decline. Nubchen authored many works, including the Lamp for the Eye in Contemplation, an extensive discussion of early Tibetan contemplative systems. But by far his longest work is his little read Armor Against Darkness, a systematic commentary on the Compendium of the Intentions Sūtra. In preparing his commentary, Nubchen studied directly under Chetsenkye and the other translators of the Compendium Sūtra.
Dargyay discusses the particular generation stage cycle of the 'Eight Pronouncements' that Nubchen was empowered to practice by Padmasambhava and through the realisation of which Nubchen accomplished the specific emanation of this Manjushri 'yidam', mandala of divine accoutrements and entourage and demonstrated his siddhi by deftly wielding the energetic phurba:
Sangs-rgyas-ye-śes practiced the gŚin-rje-snying-thig, the divine power of which is Mañjuśri; as a sign of successful meditation, he thrust a ceremonial dagger into a rock.
Lamp for the Eye in Contemplation the Samten Migdron (Tib. bSam-gtan Mig-sgron.)
Capriles in discussing the 'Lamp for the Eye in Contemplation' the Samten Migdrön discovered in 1908 at Tun-huang by Paul Pelliot states:
...this book was entombed in the ruins of Tun-huang, where it remained from the eleventh or twelfth century CE until 1908, when French Sinologist Paul Pelliot explored the cave temples that a local farmer discovered accidentally at the turn of the twentieth century. Therefore, its authenticity is beyond question.
In the Samten Migdrön, Nubchen Sangye Yeshe establishes a salient distinction within the Mahayana between:
the 'Gradual Vehicle of Bodhisattvas' ; and
the 'Sudden Mahayana' corresponding to the Dhyana, Ch’an or Zen school.
The 'suddenness' is further explicated and contextualised by Capriles who mentions Huineng:
In his sutra, Hui-neng noted that no tradition is sudden or gradual, and that these adjectives should be applied to students rather than to teachings or schools, for no doubt some students are more “sudden” than others ; however, the term is used to refer to the Ch’an or Zen School insofar as in it Awakening is not posited as the result of a gradual development through paths and levels, but as an instantaneous breakthrough.
For 'instantaneous breakthrough' and 'awakening' refer kensho and satori, respectively.
Electronic
Capriles, Elías. Buddhism and Dzogchen: The Doctrine of the Buddha and the Supreme Vehicle of Tibetan Buddhism. Part One Buddhism: A Dzogchen Outlook. Source:
Dalton, Jake. 'Anuyoga Literature' in rNying ma rgyud 'bum - Master Doxographical Catalog of the THDL. Source:
Meinert, Carmen. 'Chinesische Chan- und tibetische rDzogs chen-Lehre'. Source: http://hss.ulb.uni-bonn.de/2004/0379/0379.htm
https://journals.ub.uni-heidelberg.de/index.php/jiabs/article/download/8935/2828 Structural Analysis of the Bsam Gta Mig Sgron
Orofino, Giacomella . Sacred Tibetan Teachings on Death and Liberation: Texts from the most Ancient Traditions of Tibet. Preface by Namkhai Norbu. Bridport, Dorset, U.K.: Prism Press.