Overview
The Aparimitāyurjñāna Sūtra is among the many canonical works in which a particular buddha in another buddhafield is invoked along with the benefits of recalling his name and reciting his dhāraṇī. Associated as it is with longevity, this is one of the most widely read texts in the Kangyur, and Aparimitāyurjñāna (“Immeasurable Longevity and Wisdom”’) is one of the most frequently portrayed and well-known buddhas in the pantheon of Tibetan Buddhism.
The sūtra is commonly referred to as the Tsédo (tshe mdo, “Sūtra of Longevity”) or Tsézung (tshe gzungs, “Dhāraṇī of Longevity”), and contains a dhāraṇī that is repeated in the text twenty-nine times. It is included in many Tibetan liturgical compilations, and its recitation, usually with a specified number of repetitions, is often advised to people in poor health or facing other difficulties, or is commissioned on their behalf in monasteries.
Although its title identifies it as a sūtra, it is placed in all Kangyurs with the Action Tantras (bya ba’i rgyud, kriyātantra). In common with many other works classified as Action Tantras, there is nevertheless little in the text to identify it as a tantra. The inclusion of a long, repeated dhāraṇī in Sanskrit is presumably one criterion for this classification, although there are many other canonical works with a similar structure that are placed with the sūtras. Other criteria may have been its classification and line of transmission in India, before it was taken to Tibet, or the fact that it has also formed the basis for a wide range of tantra practices, particularly among the higher levels of tantra, in the form of sādhanas of Aparimitāyus.1
The text has also survived in a large number of Sanskrit manuscripts (mostly later Nepalese ones); in two Chinese translations; and in a different—perhaps earlier—Tibetan translation, represented by most of the very numerous manuscripts found in the caves of Dunhuang, where a Khotanese manuscript (probably the oldest surviving version) was also found.
All Kangyurs include two major versions of the sūtra, similar in most respects but differing mainly in the presence or absence of one phrase in the repeated dhāraṇī. The background of the existence of these two versions is discussed below. The version translated here is the best known and most widely used of the two, and seems to represent Sanskrit source texts brought to Tibet in the later translation period. Even this version, however, is found in two near-duplicate copies in the Degé and other Kangyurs, with one word in the dhāraṇī consistently differing between the copies.
The other major version, The Aparimitāyurjñāna Sūtra (2), Toh 675, appears to be derived from the same translation, but the dhāraṇī it contains is the shorter one, matching those found in the Chinese translations, the Dunhuang manuscript in Khotanese, and the earlier Tibetan translation represented by the majority of the very numerous Dunhuang manuscripts in Tibetan.2
This sūtra3 is one of the set known as the “ten royal sūtras,” thought to be so called either because they represent distillations of the most profound scriptures, or because according to traditional histories they were recommended to King Trisong Detsen for his daily practice by Guru Padmasambhava. As a result of practicing them, the king is said to have extended his life by thirteen years.4
In a similar vein, the fact that so many manuscript copies of this text have been found in the Dunhuang caves is due to their production by scribes there having been commissioned on behalf of Trisong Detsen’s grandson, Ralpachen (who reigned in the early ninth century), in order to ensure for the king the longevity that the text itself promises.