The Satipaṭṭhāna Sutta (MN 10) organizes mindfulness into four establishments: body as body, feelings as feelings, mind as mind, and Dhammas as Dhammas. The repeated instruction is to practice ardently, clearly knowing and mindful, having put away covetousness and grief for the world. Mindfulness is therefore not bare attention alone. It works with energy, understanding, and the abandonment of hindrances.
Contemplation of body includes breathing, posture, activities, anatomical parts, elements, and cemetery contemplations. These practices counter forgetfulness, vanity, lust, and denial of death. "Body as body" discourages turning bodily experience immediately into "my beauty, my failure, my permanent possession." The body is known according to its conditions and nature.
Feelings (vedanā) are pleasant, painful, or neutral tones that accompany contact. They are not the same as complex emotions. Knowing feeling clearly is crucial because craving commonly follows: pleasant feeling invites grasping, painful feeling invites resistance, and neutral feeling invites ignorance. The practitioner learns to know feeling without automatically obeying it.
Contemplation of mind recognizes mind with or without greed, hatred, delusion, contraction, distraction, development, collectedness, and freedom. It does not say "I am an angry person" but knows a mind affected by anger as it is. Contemplation of Dhammas uses teaching frameworks: the five hindrances, five aggregates, six sense bases, seven awakening factors, and Four Noble Truths.
Each section includes contemplating arising, vanishing, and both; internally, externally, and both; and remaining independent without clinging to anything in the world. The purpose is not constant self-monitoring for its own sake. It is clear knowledge that weakens appropriation and develops the path to Nibbāna.
The practitioner knows walking as walking, standing as standing, sitting as sitting, and lying down as lying down. Clear comprehension extends to looking, bending, dressing, eating, speaking, and keeping silent.
A pleasant feeling is known as pleasant, a painful one as painful, and a neutral one as neutral; each is further known as worldly or unworldly. The practitioner does not need to turn the tone into a command.