Four nails 繫命四釘（舊譯「肯綮四釘」或「命結四釘」，三摩地本尊釘、真言心咒釘、意不變異釘、集散事業釘，屬於大圓滿生起次第緣觀竅訣）

The four nails or “four nails that secure the life-force of the practice” (Wyl. srog sdom gzer bzhi; Tib. sok dom zer shyi), an important aspect of kyerim practice, are:

1. The nail of all appearance as the deity (nangwa lha yi zer) or the nail of concentration (samadhi) on the deity (ting nge dzin lha’i zer) or (kyerim lha'i zer)
2. The nail of all sound as the mantra (dra drak ngak kyi zer) or the nail of the essence mantra (nyingpo ngak kyi zer)
3. The nail of the activity of emanation and absorption (tro du trinlé kyi zer)
4. The nail of the unchanging wisdom mind (gongpa mingyurwé zer)

According to Nyoshul Khen Rinpoche, these four points were first taught as a special mengak by Guru Padmasambhava in the Kagyé Deshek Düpa.

Alternative Translations

• Four stakes that bind the life-force (Dharmachakra Translation Committee)
• Four stakes to bind the life-force (Erik Pema Kunsang)
• Four linchpins (Lama Chökyi Nyima)

Further Reading

• His Holiness Dilgo Khyentse Rinpoche, Pure Appearance—Development and Completion Stages in the Vajrayana Practice (Halifax: Vajravairochana Translation Committee, 2002), '5. The Four Binding Forces'. restricted publication
• Patrul Rinpoche in Deity, Mantra and Wisdom: Development Stage Meditation in Tibetan Buddhist Tantra, translated by the Dharmachakra Translation Committee (Ithaca: Snow Lion, 2007), Text Three, The Melody of Brahma Reveling in the Three Realms: Key Points for Meditating on the Four Stakes That Bind the Life-Force.
• Padmasambhava and Jamgön Kongtrül, The Light of Wisdom, Vol II, translated by Erik Pema Kunsang (Boudhanath, Hong Kong & Esby: Rangjung Yeshe, 1998), pages 108-117.