Four nails

The four nails or “four nails that secure the life-force of the practice” (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)
2. The nail of all sound as the mantra (dra drak 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)

(*) Alternatively, the first two are given as “the nail of concentration on the deity” (ting nge dzin lha’i zer) and “the nail of the essence mantra” (nyingpo ngak kyi zer)