A very popular Sutra with many people who begin their study of Zen is the Heart Sutra. It begins with:
When Avalokiteshvara Bodhisattva was practicing the profound prajna paramita, he illuminated the five skandhas and saw that they are all empty, and he crossed beyond all suffering and difficulty.
Shariputra, form does not differ from emptiness; emptiness does not differ from form. Form itself is emptiness; emptiness itself is form. So, too, are feeling, cognition, formation, and consciousness.
The original work was translated by Tripitaka master Hsuan-tsang (600–664) in 649. It is made up of 260 Chinese characters (I have two tea cups each of which has the 260 characters).
The Heart Sutra, itself, lacks a “Thus have I heard” and a proper location as is the case with all Buddhist Sutras. The Buddha makes no appearance in this Sutra, either. It should also be pointed out that Avalokiteshvara, who is he main speaker, is not mentioned in the old strata of Buddhism. For all intents and purposes, the Heart Sutra is not a Sutra. In fact, before it was translated by Tripitaka master Hsuan-tsang it was not considered to be a Sutra at all. Italics are for emphasis.
In the case of the Heart Sutra, the text before us was not considered a ching or “sutra” until Hsuan-tsang’s translation of 649. Prior to that, the text was considered a mantra or dharani, as reflected in the earlier translations of the title by Chih-ch’ien and Kumarajiva. Also, it is worth noting that none of our extant Sanskrit copies includes the word sutra in the title, and it is only reflected in the Chinese and Tibetan” (Red Pine, The Heart Sutra, p. 39).
According to Red Pine the Heart Sutra originally was a response to the teachings of the Sarvastivadins which is also Edward Conze’s conclusion as well. It was more than likely that Tripitaka master Hsuan-tsang’s translation was from Kumarajiva’s version (400 A.D.) and not Chih-ch’ien’s version which was reported to have been missing as early as 519.