Introducing your true nature.
It is crucial to have a grounded understanding of the four noble truths in order to appreciate the Dzogchen view and practice. The four noble truths teach us to:
Understand the human predicament.
Let go of the arising of attachment, aversion and ignorance.
Actualize the state of cessation.
Practice the path.
In the first turning of the wheel of dharma, the Buddha did not go into great detail on the third noble truth of actualizing or beholding the state of cessation. In the first turning, the Buddha described the state of cessation as what it was free from, namely attachment, aversion and ignorance. He did not go into depth about the actual experience of that state.
In the second turning of the wheel of dharma he made it more clear by introducing the five features of emptiness, but even this is a more conceptual and elaborate way of understanding and recognizing the truth of cessation. By understanding the relative and ultimate truth, we can better understand the nature of the mind and gain clarity about the resultant state of the nature of our own mind.
In the third turning, the Buddha explicitly described the truth of cessation, introducing the tathagatagarbha or buddha heart. By understanding our primordial state as originally pure and ever-present, the resultant state is not something newly acquired but instead something that we come to recognize or reawaken. It is as though we have lost something for a long time, only to find it and at that same moment experience complete resolution and certainty.
The third turning of the wheel of dharma and the teachings on the tathagata-garbha opened the door to the Vajrayana, including practices like Buddhist tantra, Mahamudra and Dzogchen. Tantra introduced the buddha heart as something to purify and transform. It is only in Mahamudra and Dzogchen that we find the completely unelaborate introduction to the nature of the mind itself as the basis of the path. While Mahamudra and Dzogchen are similar in many aspects, they do have critical differences in terms of method of introduction and differences in working with the resultant state of awareness.
Dzogchen, or the Great Perfection, is a direct introduction to our primordial state of authentic presence, our intrinsic awareness or rigpa in Tibetan. However, being introduced to rigpa is not enough, we must engage in the practice of Dzogchen in order to actualize the resultant state of awareness. Garab Dorje introduces the Dzogchen path in this Three Statements that Strike the Vital Point:
One is introduced directly to one's true nature,
Be decisive about this unique state,
Continue directly with confidence in liberation.
The teacher directly introduces the student to their intrinsic awareness, or rigpa, which is the primordial state of authentic presence. There are many methods and teachings which can introduce rigpa, my own teacher Younge Khachab Rinpoche wrote a short mind treasure entitled Drop of Secret Nectar which introduces the primordial state of rigpa. When one has recognized rigpa in their own experience, they can study Longchenpa's Way of Abidingto gain a deeper understanding of that state as the four samayas of Dzogchen.
After one has been introduced to rigpa and recognized that primordial state of being, you need to be decisive about this unique state. This can only be resolved through the practice of meditation, in which you work with and resolve all that appears and exists. As you learn to work with the unceasing display of the primordial state, you move through the practices of trekchod to come to a decisive experience of one's own nature as the unborn awakened mind, or ultimate bodhicitta. Longchenpa's masterpiece on coming to the decisive experience of awakened mind can be found in the first nine chapters of the Choying Dzod, the Treasury of the Basic Space of Phenomena.
Having come to a decisive experience of rigpa, our own primordial state of authentic presence, one perfects the practice of trekchod and the practice of thogal naturally unfolds as one continues with confidence in liberation. Much can be said about the practice of thogal, and of course their are books to read, but by the time you get to this state in your practice you recognize that you already have all the teachings you need. You have been decisive after all, haven't you?
The easiest part of Dzogchen is the introduction. You can get introduced to your own awareness as the primordial state of being. You can be introduced to the result, the truth of cessation, directly, in your own experience. Many do, and then they leave it at that. Off to the next thing. Just like meeting a person and then later forgetting their name, the introduction itself it not enough.
The hardest part of Dzogchen is to be decisive about this unique state. That second point of Garab Dorje's. Padmasambhava, the "Guru Rinpoche" who brought the Vajrayana to Tibet, spent twelve years contemplating Dzogchen in the charnel grounds of India after he was introduced to his primordial state by Shri Singha. Twelve years for one of the greatest Dzogchen masters. If you want to practice Dzogchen, much less realize the natural Great Perfection, you need to meditate. Demand clarity in your practice. Demand confidence in your realization. Be decisive. Then you continue with confidence in liberation, which connects back to the fourth noble truth. Practice the path.