Amoghavajra and the Indian Calendar in Chinese

The zodiac Cancer.
It was in the year 764 as part of his compilation of the Xiuyao jing 宿曜經 (T 1299) that the Vajrayāna master and translator Amoghavajra 不空 (705-774) translated the Indian lunar calendar into Chinese with with his assistant Yang Jingfeng 楊景風, a Chinese court official who later was involved in official calendar reforms. The latter added notes to explain the differences between the two systems. While both are lunar rather than solar, they still differ considerably.

Unlike the numbered system of months and days in Chinese, the Indian lunar calendar uses a sequence of 27 (or 28) constellation (nakṣatra) names, which represent the zones the moon travels in a month before returning to its original place. In ancient China they likewise had a similar system of 28 constellations (the xiu 宿), though those stars do not really match the ancient Vedic model, if it is even possible to reliably compare them since the Vedic literature doesn't provide accurate coordinates and later Indian star catalogs are inconsistent (see David Pingree's article "Identification of the Yogatārās of the Indian Nakṣatras" here). Nevertheless, it seems the inspiration for such models had a common source, which was probably Babylon though there is no such evidence proving this to my knowledge. This remains a significant mystery in Asian history.

The 27 nakṣatra-s paired with the Chinese constellations are as follows:

1.  婁宿 Aśvinī
2.  胃宿 Bharaṇī
3.  昴宿 Kṛttikā
4.  畢宿 Rohiṇī
5.  觜宿 Mṛgaśīrṣa
6.  參宿 Ārdrā
7.  井宿 Punarvasū
8.  鬼宿 Puṣya
9.  柳宿 Aślesā
10. 星宿 Maghā
11. 張宿 Pūrvaphālgunī
12. 翼宿 Uttaraphālgunī
13. 軫宿 Hasta
14. 角宿 Citrā
15. 亢宿 Svāti
16. 氐宿 Viśākhā
17. 房宿 Anurādhā
18. 心宿 Jyeṣṭha
19. 尾宿 Mūla
20. 箕宿 Pūrvāṣāḍhā
21. 斗宿 Uttarāṣāḍhā
22. 女宿 Śravaṇa
23. 虚宿 Dhaniṣṭhā
24. 危宿 Śatabhiṣaj
25. 室宿 Pūrvabhādrapadā
26. 壁宿 Uttarabhādrapadā
27. 奎宿 Revatī

In the 28 nakṣatra model, before Śravaṇā is one more constellation: 牛宿 Abhijit. The 27 model was initially used in Amoghavajra's work, though later editors of his work in China added the extra constellation, presumably because it suits the Chinese model which is strictly 28 constellations. The Indians could use either, though the 27 model allows for an equal division into 3 parts of 9, which is perhaps astrologically significant.

In the Indian model the month commences from the full moon, unlike with the Chinese lunar calendar where it starts from a new moon. Also, as Yang Jingfeng states in India "the month is always named based on which constellation (nakṣatra) the moon is in on the night of the fifteenth day of the śukla-pakṣa" (i.e., the last day of waxing or the full moon), hence the months are called Citrā, Viśākhā, Jyeṣṭha, Pūrvāṣāḍhā and so on (see below). In Chinese reckoning, this would be the 15th day of the month (wang 望), since the 1st is the new moon (shuo 朔). The waning period would run from the 16th-30th, which is the kṛṣṇa-pakṣa. In the Indian calendar the 30 day month is divided into the two pakṣa-s, which are also astrologically significant according to Buddhist scripture.

For instance, the Chinese translation of the Four Deva Kings Sūtra 四天王經 (*Catur Devarāja Sūtra) – which is also quoted in Nāgārjuna's (c. 2nd-3rd cent.) Mahāprajñāpāramitā Upadeśa – details how the Four Mahārāja under Indra's direction descend with their entourages to inspect the world and its inhabitants:

The devas on the fasting days examine the good deeds and misdeeds of people. Atop Mount Sumeru there is the second [desire realm heaven] of Trāyastriṃśa where there is the celestial sovereign named Indra whose virtues are lofty. The chief four devas, the four deva kings, are Indra's four guardian kings, each managing one direction. On the eighth day of the month envoys are always dispatched who descend on an inspection tour of the whole world. They investigate the sovereigns, kings, officials, citizens, nāgas, spirits, fliers, crawlers and wrigglers – the good deeds and misdeeds in the thoughts of their minds, the speech of their mouths and the actions of their bodies. On the fourteenth day he dispatches the princes who descend. On the fifteenth day the four kings themselves descend. On twenty-third day the envoys again descend. On the twenty-ninth the princes again descend. On the thirtieth day the four kings again personally descend.
The text was translated into Chinese by Zhiyan 智嚴 and Baoyun 寶雲 in 427. It is clear here that they converted the Indian two 15 day pakṣa model into the Chinese 30 day model. In any case, this belief in various gods descending into the world or inspecting it on specified days of the month is found in other Indian Buddhist texts as well, which should be noted are not Mahāyāna like the Abhidharma Mahāvibhāṣā Śāstra, attributed to Kātyāyanīputra. This work is generally held to have been composed sometime around the 2nd century CE in northwest India, and moreover was a key treatise of the Sarvāstivāda school in Kashmir. See the following:

Question – Why only speak of thirty-three devas? Answer – The devas frequently gather to discuss good deeds and misdeeds. Hence the partial discussion of them. The devas during the waxing and waning periods, on every eighth, fourteenth and fifteenth, always gather in the Hall of Saddharma to weigh the amount of good deeds and misdeeds in the world. Furthermore, the thirty-three devas constantly together inspect the creators of good deeds and misdeeds. Seeing one who has created good deeds, they then protect them. Seeing one who has created misdeeds, they then together resent and ruin them.

This system was understood easily enough for the Chinese who had a lunar calendar of their own, but the more advanced model provided by Amoghavajra with specific month and day names was more complex. The first draft of this manual in 759 wasn't readily understood by Amoghavajra's Chinese colleagues, so they revised it using a table, which I've reproduced using the original Sanskrit nakṣatra names (click here for full image file):

This is a brilliant example of cross-cultural intellectual exchange between the Indosphere and Sinosphere in pre-modern times. Amoghavajra took the time with his colleagues to carefully translate the Indian calendar into Chinese terms. The text also introduces the concept of weekdays, which was alien to the Chinese but important for esoteric Buddhism as well as Zoroastrianism and Manichaeism, which is why the names for weekdays in Persian and Sogdian are provided in transliterated Chinese so people could ask a foreigner what day of the week it was. For instance, Venus for Friday in Sogdian: na xie 那頡 = n'xyẟ ).

This is one part of my present research, which is exploring how occidental astrology was introduced and employed in China in the Tang dynasty (618-907). I am also in the process of translating this Xiuyao jing into English. While this should be of interest to Sinologists, the work is actually an important period specimen detailing Indian astrology from the eighth century. Only a fraction of such classical Indian literature is available in Sanskrit, which highlights the importance of Indian literature preserved in other languages like Chinese and Tibetan.

No comments :