Yijin Jing

The Yijin Jing (simplified Chinese: 易筋经; traditional Chinese: 易筋經; pinyin: Yìjīnjīng; Wade–Giles: I Chin Ching; literally: "Muscle/Tendon Change Classic") is a manual containing a series of exercises, coordinated with breathing, said to enhance physical health dramatically when practiced consistently. In Chinese yi means "change", jin means "tendons and sinews", while jing means "methods". While some consider these exercises as a form of Qigong, it is a relatively intense form of exercise that aims at strengthening the muscles and tendons, so promoting strength and flexibility, speed and stamina, balance and coordination of the body. In the modern day, there are many translations and distinct sets of exercises all said to be derived from the original (the provenance of which is the subject of some debate). These exercises are notable for being a key element of the physical conditioning used in Shaolin training.

According to legend, the Yijin Jing was said to be left behind by Bodhidharma after his departure from the Shaolin Monastery, and discovered within his grave (or hidden in the walls of the temple) years after he had left (or died). It was accompanied by another text, the Xisui Jing, which was passed to a student of Bodhidharma's, but has not survived to the modern day.

The monks of Shaolin supposedly practiced the exercises within the text but lost the true purpose of the document; Lin Boyuan recounts the legend that they "selfishly coveted it, practicing the skills therein, falling into heterodox ways, and losing the correct purpose of cultivating the Way. The Shaolin monks have made some fame for themselves through their fighting skill; this is all due to having obtained this manuscript."

Both documents were written, per the mythology, in an Indian language which was not well-understood by the monks of the temple. According to one legend, a monk decided that the text must contain more valuable knowledge than simply self-defense, and went on a pilgrimage with a copy of the text to find someone who could translate the deeper meaning of the text. He eventually met an Indian priest named Pramati in the province of Szechwan who, examining the text, explained that the meaning of the text was extraordinarily deep and beyond his ability to translate fully. He nonetheless provided a partial translation. The monk found that within a year of practicing the techniques as Pramati had translated, that his constitution had become "as hard as steel," and he felt that he could be a Buddha. The monk was so pleased that he thereafter followed Pramati wherever he went.

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