三身 (Skt trikaya; Jpn san-jin )
Three kinds of body a Buddha may possess. A concept set forth in Mahayana Buddhism to organize different views of the Buddha appearing in the sutras.
The three bodies are as follows:
(1) The Dharma body, or body of the Law (Skt dharma-kaya ).
This is the fundamental truth, or Law, to which a Buddha is enlightened.
(2) The reward body (sambhoga-kaya), obtained as the reward of completing bodhisattva practices and acquiring the Buddha wisdom.
Unlike the Dharma body, which is immaterial, the reward body is thought of as an actual body, although one that is transcendent and imperceptible to ordinary people.
(3) The manifested body (nirmana-kaya), or the physical form that a Buddha assumes in this world in order to save the people. Generally, a Buddha was held to possess one of the three bodies.
In other words, the three bodies represented three different types of Buddhas—the Buddha of the Dharma body, the Buddha of the reward body, and the Buddha of the manifested body.
On the basis of the Lotus Sutra and the principle of three thousand realms in a single moment of life derived from it, T'ient'ai (538-597) maintained that the three bodies are not separate entities but three integral aspects of a single Buddha.
From this point of view, the Dharma body indicates the essential property of a Buddha, which is the truth or Law to which the Buddha is enlightened.
The reward body indicates the wisdom, or the spiritual property of a Buddha, which enables the Buddha to perceive the truth.
It is called reward body because a Buddha's wisdom is considered the reward derived from ceaseless effort and discipline.
The manifested body indicates compassionate actions, or the physical property of a Buddha.
It is the body with which a Buddha carries out compassionate actions to lead people to enlightenment, or those actions themselves.
In discussing the passage in the "Life Span" (sixteenth) chapter of the Lotus Sutra that reads, "You must listen carefully and hear of the Thus Come One's secret and his transcendental powers,"
T'ient'ai, in The Words and Phrases of the Lotus Sutra, interpreted "secret" to mean that a single Buddha possesses all three bodies and that all three bodies are found within a single Buddha.
see also: Trikaya