From The Shambhala Dictionary of Buddhism and Zen translated by Michael H. Kohn; © 1991 by Shambhala Publications, Inc. Reprinted by arrangement with Shambhala Publications, Inc., www.shambhala.com
Skt., lit., “thread”; (Pali, sutta; Jap., kyō); discourses of the Buddha. The sūtras are collected in the second part of the Buddhist canon, the Sūtra-pitaka, or “Basket of the Teachings.”
The sūtras have been preserved in Pali and Sanskrit, as well as in Chinese and Tibetan translations. According to tradition they derive directly from the Buddha. The sūtras are prose texts, each introduced by the words “Thus have I heard.” These words are ascribed to Ānanda, a student of the Buddha. He is supposed to have retained the discourses of the Buddha in memory and to have recited them at the first Buddhist council, immediately after the death of the Buddha. After these introductory words, the circumstances that occasioned the Buddha to give the discourse are described, as well as the place, the time of year, etc. Then the actual instruction follows, sometimes in the form of a dialogue. The style of the sūtras is simple, popular, and didactically oriented. They are rich in parables and allegories. In many sūtras, songs are interpolated. Each sūtra constitutes a self-sufficient unit.
The Hīnayāna sūtras are divided into “collections,” which in the Pali canon are called Nikāyas and in the Sanskrit version, Agamas. The Nikāyas are the Dīgha-nikāya, Majjhima-nikāya, Samyutta-nikāya, Anguttara-nikāya, and Khuddaka-nikāya.
Along with these Hīnayāna sūtras, a great number of Mahāyāna sūtras have also been preserved. They were originally composed in Sanskrit but are for the most part extant only in Chinese or Tibetan translations. They are thought to have been composed between the 1st century BCE and the 6th century CE. They adopted the external form of the Hīnayāna sūtras—they also begin with the words Thus have I heard and a description of the place, occasion, and the persons present. Three types of Mahāyāna sūtras are differentiated: Vaipulya-sūtras, dhāranīs, and independent sūtras.