Walking, sitting, and lying down — what is the difference?

While walking, the body consciousness and mind consciousness should be placed on the operation of the physical body, with attention on the body and the surrounding environment; the attention of the solitary mental consciousness for contemplating the meaning of the Dharma must be reduced—there is not enough energy, one cannot be single-minded, the contemplation is not deep and subtle, and wisdom does not easily arise. Whereas in sitting and lying down, the consciousnesses are less scattered, the solitary mental consciousness can concentrate more, the contemplation becomes deep, subtle, and meticulous, and wisdom arises more easily.

Therefore, it is said that the stillness-based meditative concentration of sitting and lying down more easily gives rise to wisdom. In sitting and lying down, the mind has no extra burdens, so one can concentrate one's energy and contemplate subtly and meticulously, without worrying about what situations walking might encounter. With the mind at ease, it is easier to attain preparatory concentration (anāgamya-samādhi) and first dhyāna concentration while sitting in stillness.

Wisdom arises from meditative concentration, and this concentration refers to preparatory concentration and first dhyāna concentration. Therefore, for attaining the fruits and enlightenment, one must at minimum possess preparatory concentration. As long as it is not a thought-free preparatory concentration or first dhyāna concentration, with deep concentration the contemplation becomes even more meticulous, and there is no problem in opening wisdom and discovering a new continent.