Long Scroll of the Treatise on the Two Entrances and Four Practices

The Treatise on the Two Entrances and Four Practices (Chinese: 二入四行; Pinyin: èrrú sìxíng; Wade-Giles: Erh-ju ssu-hsing; Japanese: Ninyū shigyō ron) is a Buddhist text attributed to Bodhidharma, the traditional founder of Chan (Japanese: Zen) Buddhism.

The text, sometimes referred to simply as The Two Entrances, was first used in 6th century CE by a group of wandering monks in Northern China specializing in meditation who looked to Bodhidharma as their spiritual forebearer. Though this text was originally attributed to Bodhidharma, a great deal of material was added to it, probably around the 8th century, by the monks or perhaps other anonymous groups. The work, along with T'an Lun's biography of Bodhidharma and other newly discovered manuscripts, was recompiled by a Japanese Zen practitioner, Suzuki Daisetsu, in 1935.

The two entrances referred to in the title are the entrance of principle (理入 lǐrù) and the entrance of practice (行入 xíngrù).

The format of the text is that of a collection of the master's teaching as collected by his students. There are two entrances listed, one abstract and one concrete. In other words, the text list two different ways of achieving enlightenment, one based on inward reflection (the entrance of principle) and one based on outward action (the entrance of practice). The bimodal structure of this treatise was frequently copied and became typical in early Chan Buddhism.

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