What are the Three Trainings and how are they practical? Specifically how does one practice them?
The threefold training (Pali: sikkha) consists of: morality (sila); concentration (samadhi); and wisdom (panna).
Sikkha is meant to conquer and eradicate the defilements (kilesas).
'The defilements are the ten states, namely: greed; hate; delusion; conceit; false view; uncertainty; stiffness of mind; agitation; conciencelessness, shamelessness. They are so called because they are themselves defiled and because they defile their associated states.'
Each of those defilements has 3 stages (bhumi) which are identical to the 3 stages of consciousness (latent - manifested - action).
- the latent stage = anusaya-bhumi
- the manifest stage = pariyutthana-bhumi
- the action stage = vitikkama-bhumi
Through the threefold training, it is possible to conquer and eradicate these defilements in the 3 subsequent stages: sila-sikkha; samadhi-sikkha; and panna-sikkha.
The training itself is a strict personal affair: Purity and impurity depend on oneself. No one can purify another (Dhammapada).
The Three (Higher) Trainings are:
Ethics Concentration Wisdom
The practice of ETHICS entails abandoning negative actions of body, speech and mind (such as killing, stealing, lying, sexual misconduct, intoxicating the body, harmful speech, greed, etc). And cultivating virtuous actions of body, speech and mind (generosity, patience, gentle speech, etc).
The practice of CONCENTRATION entails developing single-pointed attention on a meditative object (such as the sensations of the breath, a mental image, thoughts and the space of the mind, etc) by cultivating relaxation, stability and vividness. There are 9 stages for the this practice (shamatha) and the culmination is a refined mind that experiences bliss, clarity and non-conceptuality. At this point you are able to focus your attention effortless for long periods (4 hours or more) without any distraction or internal chit-chat, this state is called samadhi.
The practice of WISDOM entails, gaining insight into the nature of reality, this means understanding experientially and not only conceptually how all phenomena and oneself exist. Everything exists as an interdependent matrix of causes and effects, and everything is empty of inherent existence.
The first step is to begin practicing the Four Applications of Mindfulness: Applied Mindfulness to the body, feelings, mental events and phenomena. These practices imply not only being mindful of the body sensations, thoughts, etc, but also to develop wisdom by questioning if these things exist as we perceive them or if they are impermanent, interdependent and lacking an inherent, real, solid existence. After becoming good at these practices you can also practice analytical meditation, debate, and Dream yoga to start questioning the solidity of what you call reality.These practices are called Vipashyana and one applies them also to the I, until one finds that one doesn't exist as an independent ego, but as a matrix of interrelated phenomena and that we also lack inherent existence. There's a risk here to think we don't exist at all and becoming depressed or nihilistic, so it's important to practice also Dzogchen, Mahamudra or similar practice to understand and realize that we are pure awareness and by recognizing this primordial consciousness we transcend the concepts of existence and non-existence and we become enlightened.
This insights can only be sustained if you have achieved single-pointed concentration (shamatha) first, otherwise with an unbalanced, wandering mind trying to develop wisdom is not possible. And concentration can only be achieved if one lives an ethical way of life, because a mind that is filled with mental afflictions such as anger, craving, greed, attachment, ignorance, arrogance, etc, is a wandering mind unable to find peace and develop concentration, furthermore an afflictive mind is ignorant and unable to develop wisdom.
The Three Trainings in Buddhism are the most important, organizing feature in Buddhism.
Everything that is not related to the 2nd and 3rd training is called the 1st training: morality.
This is related to learning to live life correctly, having Right Livelihood, developing communication skills with others, forgiving others, thinking about how to enjoy time with friends, choosing friends, etc.
Basically, success in the 1st training means doing good in the world, for ourselves and others.
The best way to understand what the 1st training is, is to understand the 2nd and 3rd trainings and understand that the 1st training is what the 2nd and 3rd training is not. These latter two trainings have a much simpler definitions and are also very important in spiritual growth because they are very much in our locus-of-control.
The 2nd training is concentration. This training involves any meditation practice which makes one calmer, more blissful and directed towards the five qualities of jhana. The success in this training contains mastery of the entire range of form and formless jhanas.
The 3rd training is wisdom. This training is synonymous with vipassana and involves any meditation practice which trains one in becoming more present and noticing of the 3 Characteristics. The success in this training contains mastery of the Stages of Insight, which has a continuous and recursive process to it and blossoms in Awakening/Fruition.
Since the 2nd and 3rd training deal with samatha and vipassana meditation respectively, the 1st training, as mentioned earlier, deals with the good work we do in the rest of our lives.
This is a wonderful organizing structure because of the fact that most of what we do in our daily lives falls into the 1st training and this type of understanding can help us prioritize. For example, participating on SE Buddhism, conversing with online forums, and participating in a local Sangha is the 1st training and we should continue to do so... but we should neglect our Practice, namely the 2nd and 3rd training.
The Three Trainings are also mutually supportive of each other and improving in any training is definitely going to cause an improvement in the other trainings so they should all be worked on simultaneously. This mutual support raises more interest questions like what category does brahma meditation would fall under? and why does vipassana sometimes seem like jhana?
It's not the point to categorize everything into this system. What's important is that one not be too involved in the 1st training and realize that the training in concentration and wisdom are very important in Buddhism and lead directly to the goal of Buddhism. Also these two trainings take a lot of time (e.g. 3 year meditation retreats).
For more info on this idea see "Mastering the Core Teachings of the Buddha."