srog sdom gzer bzhi
the four life-binding nails [IW]
four stakes to bind the life-force (srog sdom gzer bzhi) - [detailed expl., The Light of Wisdom, Vol. 2, page 108]. Furthermore: To explain the four stakes to bind the life-force, the object to be purified is the state of affairs of a sentient being's body, speech and mind as well as its activities. The result of purification is the Body, Speech, Mind, Qualities and Activities of buddhahood. Even though this basic state of affairs of any sentient being is primordially pure as these aspects of buddhahood, in the apparent state these are seen as being impure and involved in the cause and effect of samsaric existence. The means which purify are to apply these key points of instruction to these four stakes which bind this life-force and herein you come to realize the way it ultimately is. Thus, by binding samsara and nirvana with the life-force of their purity in being completely equanimous, both the basic and the apparent aspects - the practitioner's three gates and Activities and the deity's Body, Speech, Mind and Activities - are brought into the path as the great primordial purity. This is therefore the extraordinary key point of the nonseparateness of development stage and completion stage and the special feature of the Old School of the Early Translations, Ngagyur Nyingma. Dilgo Khyentse Rinpoche [RY]
four nails which control life-breath [RY]