The trunk: the Mahamudra of the Amulet Box
Adapted from a booklet by Prof. Matthew Kapstein - which encourages copying and free distribution:
The trunk: the Mahāmudrā of the Amulet-Box (sdong po phyag chen ga'u ma)
The scholar-saint Khyungpo Naljor was exceedingly proud of the Vajrapadas which contain the precepts of the essential points which can not be formulated intellectually. He therefore inserted the paper rolls upon which they had been written into a small Nepalese amulet-box and wore them around his neck. Thus these precepts became known as the "Mahāmudrā of the Amulet-Box". One first cultivates tranquility (zhi gnas) and insight into the nature of reality (lhag mthong) by way of the preliminary pratice of "The natural disposition of Body, Speech and Mind" (rang babs gsum). Then, in the fundamental practice, the calling down of the vajra-like primordial awareness causes one to steal a glimpse which introduces the Mahāmudrā, whereupon, through the natural dissolution of the four faults (which would otherwise obstruct further progress), all doubts in respect to the nature of mind-as-such are resolved. In the final practice, one sustains the three Kayas which have come about spontaneously and, by relying on extraordinary means of boosting the practice and removing obstacles, the Mahāmudrā, which is the heart of the doctrines of all Sutras and Tantras, as well as the very essence of all meditational precepts, becomes fully manifest as the natural liberation which is the realisation of the four Kayas.
As mentioned above, the "Amulet-box Mahāmudrā" is called thus because Khyungpo Naljor kept and wore the instructions in such a box around his neck. To this Taranatha adds: "There are many who wish to introduce all sorts of more profound or esoteric explanations for its name, such as 'the jewel of mind is inserted into the amulet-box of means and wisdom.' All of that talk is just meaningless gossip and an expression of confusion!"