唐宋曆日祭祀吉日鋪注的變化與適用範圍——以「神在」日為中心的探討

Changes to the Arrangement and Suitable Range of Auspicious Days for Sacrifices in Calendars between the Tang and Song Dynasties: A Study of Shenzai Days

唐宋曆日中祭祀吉日鋪注的基本原則有重要的變化。現存中日文獻顯示，初唐至大衍曆施行期，國家曆日鋪注祭祀吉日的基本依據是以特定干支日為吉日的「神在日」，且須迴避凶會神煞、月煞所在日。中晚唐時期，由於中央王朝對一些地方控制力減弱，加以一些學者重新定義「神在日」所在的干支，出現了多種「神在日」，天罡、河魁取代凶會神煞成為曆日鋪注祭祀吉日必須避忌的神煞。地方行用的一些曆日中，祭祀吉日鋪注遂發生了變化。可能是在宋真宗時期，官曆中開始用現見於元曹震圭《曆事明原》中的唐賈耽所集「神在日」作為鋪注祭祀吉日的基本依據，至遲在南宋淳熙時期，已經在曆日中的每日之下鋪注「神在」字樣。南宋官曆中避忌的神煞也與唐代有重要差別，例如除天罡、河魁之外，建日、破日也被避忌，凶會神煞和月煞不再被避忌。而宋代民間選擇典籍中祭祀需要避忌的神煞大量增多，遠超官曆。因此國家頒曆鋪注神在日和諸多神煞，一方面是吸收了晚唐五代以來民間流行的觀念，另一方面則對民間流行的避忌有規範和制約的企圖。「神在日」對唐代國家祭祀幾乎沒有影響，對北宋國家需要擇日的祭祀有一定影響，對南宋國家祭祀的影響又呈下降態勢。官曆中鋪注的祭祀吉日主要針對的是非國家祭祀，有證據表明，在社會上確有重要影響，但不及於佛教和道教。

The methodology for identifying auspicious sacrifice days in calendars changed in important ways between the Tang and Song dynasties. Extant documents in Chinese and Japanese show that from the early Tang to the implementation of the Dayan Calendar (大衍曆), the fundamental basis for selecting auspicious days in national calendars was to choose shenzai days (神在日), which were in turn preselected auspicious days in the ganzhi system; xionghui shensha (凶會神煞) and yuesha (月煞) days were to be avoided. In the middle to late Tang period, different shenzai days were identified due to the central government’s weakening control over some localities as well as a change in the definition of shenzai days by some scholars; moreover, tiangang (天罡) and hekui (河魁) days replaced xionghui shensha and yuesha days as the inauspicious shensha days to be avoided. These developments changed the selection of auspicious sacrifice days in certain local calendars. During the reign of the Song emperor Zhenzong (r. 998-1022), it is likely that Tang scholar-official Jia Dan’s 賈耽 collection of shenzai days became the basis for the arrangement of auspicious sacrifice days in national calendars. By the Chunxi era (1174-1189) at the latest, auspicious days were labeled with the characters shenzai in national calendars, while inauspicious days included tiangang, hekui, jian (建), and po (破) days, but not xionghui shensha or yuesha days. In folk almanacs during the Song dynasty, inauspicious shensha days on which to avoid sacrifices far outnumbered those in national calendars. Regarding the selection of both auspicious and inauspicious days, national calendars in the Song incorporated folk ideas that were popular from the late Tang to the Five Dynasties periods in an effort to standardize and circumscribe practices. Shenzai days had almost no impact on state sacrifices in the Tang dynasty but had some influence on the selection of days in the Northern Song. By the Southern Song, however, that influence had waned. Finally, auspicious days identified in official calendars were considered suitable for non-state sacrifices only; and they did have considerable influence on society at large, although they were also not considered suitable for Buddhist or Daoist ceremonies.