In regarding to Nighthawk' s question, What does "Rushan" practice consist of, i did put here on the Bon forum some elucidations.
Here follows a brief explanation about the Rushen, done by John Reynolds. We have seen that somewhere else on this forum, the preliminaries are not seen as per se necessary regarding the Direct Introduction (DI).
But the preliminaries are in Bon Dzogchen and Nyingma, certainly very important because there is a difference between the mind of + karma and - karma, dualisms (sems) and the Nature of Mind (sems-nyid), which is without the characteristics of the former mentioned mind. It are also clear 2 different words for mind seen as the mind of karma and ego and the mind which is freed if that.
So the gradual approach to the Direct Introduction, is here at the Bon forum, seen as the safest way to get emancipated.
In general, the Rushans, both:
are preliminary exercises in the Dzogchen tradition that prepare the practitioner for a direct introduction to the intrinsic Awareness that is the characteristic of the Natural State (rig-pa ngo-sprod). As with the Nyingmapa tradition, for example, in the kLang-chen snying-thig system of Jigmed Lingpa, the Rushan exercises have the function of leading the practitioner to distinguish between the mind (sems) or thought process and the Nature of Mind (sems-nyid) that lies beyond the operations of mind.
Thus, the full name for these exercises is 'khor 'lias ru-shan dbye-ba, "the distinguishing between Samsara and Nirvana," where Samsara indicates mind, or the ever cyclical thought-process, and Nirvana indicates the Nature of Mind.
The inner Rushans found in the text by Jigmed Lingpa also serve to purify the 6 realms of rebirth, as do the Bonpo exercises presented here.
Internal Rushen is the purification of the 6 lokas with visualizations and the purification of our emotions according Lopon Tenzin Namdak Rinpoche.
The instructions for the Outer Rushans are not included in the text here and are normally only given orally.
The first text, Rigs drug rang sbyong gi gdams-pa "The Instructions for the Self-Purification of the 6 Realms", describe in detail these exercises, where one meditates on the 6 deities known as Dulshen ('dul gshen drug) who are the guides for beings in the 6 realms of rebirth. These 6 sages, who subdue and convert beings, are all regarded as emanations of Tonpa Shenrab projected into the 6 different realms or destinies of rebirth. They correspond to the 6 Munis in the Buddhist system of the Tibetan Book of the Dead.
The 2nd text, sKu lnga rang-khrid , "SelfInstruction on the 5 Bodies," pertains to meditation on the 5 Pure Deities and their Consorts. These deities correspond, more or less, to the 5 Dhyani Buddhas and their Consorts in the Buddhist system of the Tibetan Book of the Dead. They represent the purification of the 5 skandhas or aggregates of conscious experience in the form of the 5 Buddhas and the purification of the 5 material elements in the form of the 5 Consort Goddesses.
Because they involve more elaborate visualizations, these Inner Rushan exercises appear to be more related to the Tantric system than Dzogchen.