The Satipatthana Sutta is a famous Buddhist scripture attributed to the Buddha (although it is unlikely it was actually spoken by the Buddha but instead is a compiling of various teachings of the Buddha). The Satipatthana Sutta is used for instruction in very basic meditation training (rather than used for very advanced training).
The Satipatthana Sutta is often interpreted and thus taught differently by different teachers.
The word 'satipatthana' means 'establishing mindfulness'. Establishing 'mindfulness' means to 'bring to mind' the Buddhist teachings in relation to experience. In terms of formal 'satipatthana' practise, it means to not have greed, grief or attachment towards experience. The Satipatthana Sutta says as its core practise:
he lives clearly comprehending and mindful, having overcome, in this world, covetousness and grief.
he lives detached and clings to nothing in the world.
Satipatthana practice includes the natural experiencing of four objects:
(i) the breathing & body;
(ii) pleasant, painful & neutral feelings;
(iii) the mind, its moods or, otherwise, its clarity; and
(iv) various realities ('dhamma'), such as impermanence, the nature of suffering & peace, etc.
These four objects of meditation experience are used to train mindfulness; so to remember to not cling or have greed or grief towards these four objects.
Importantly, continuously experiencing the breathing & body with a non-attached and non-judging mind causes the breathing to calm & the body to relax. In short, it feels peaceful & calm.
Ideally, Satipatthana requires having normal breathing and being able to sit still with back upright (either cross-legged on the floor or in a chair without leaning against the back of the chair) for about 30 to 60 minutes. Having normal breathing means not having a blocked nose or any other chronic breathing abnormality. Having normal breathing & sitting upright allows the breathing to relax & calm while keeping the mind alert and non-drowsy.
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