<論説>室町時代の災害と伊勢神宮 (特集 : 災害)

Abstract

国家の宗廟たる伊勢神宮では、災異が発生した際には、朝幕から祈祷命令が出されて祈祷が行われた。九世紀に怪異に対する国家の対処方法が確立されて以降室町時代までは、伊勢神宮において境内の木が倒れたり、社殿の千木が折れたり屋根が崩落したりすると、それは怪異とみなされて朝廷に報告された。そして朝廷では軒廊御トを行って怪異の原因が追及され、奉幣などの対応がなされた。神社にとって重要なのは、社殿が整っていて清浄な状態にあることであり、祭祀が決められたとおりに挙行されることによってカミは力を発揮することができた。ゆえに怪異・災害と遷宮は連動しており、中世の伊勢神宮では仮殿遷宮が頻繁に行われた。中世社会においては、災害は単なる自然現象ではなく、カミの意思のあわわれであって、カミの意思を推し量って災害を鎮めることが求められた。

At Ise Jingu, a mausoleum (sobyo) of the imperial progenitor, prayers were conducted whenever orders for such prayers, which had been issued by the court or the bakufu, were received. The orders were issued by the authorities whenever disasters or uncanny events occurred somewhere in Japan. From the time in the 9th century, when the national policy for responding to uncanny events was established, until the Muromachi period, when mysterious phenomena would occur at Ise Jingu--trees within the precincts would topple, or the roof of the main shrine building would be smashed by falling trees; these would be deemed uncanny events and reported to the imperial court. The court would then investigate for precedents, have officials of the Jingikan (Office for Worship of Native Divinities) and the Onmyoryo (Bureau of the Ying-Yang Practitioners) conduct divinations, called Konro no miura, to determine the cause, and report on possible evil omens of future reoccurrences. Then, on the bases of these reports, high-ranking nobles would conduct exorcisms in an attempt to cope with these uncanny events. When the Konro no miura divinations were rendered, the result was often "a violation of the native kami; an impure pollution, " and in response offerings to the shrine or repairs of the main shrine building would be carried out. Uncanny events were thought to be representation of the kami's intent, i. e. the divine will, and throughout medieval society, the state attempted to prevent crises before they arose by interpreting these signs. Medieval Japan was a divine country, and as was recorded in the Goseibai shikimoku legal codes, it was thought that, "the authority of the kami was increased by the respect of the people, and the fortune of the people was multiplied by the virtue of the kami." Thus it was a particularly important task to preserve the purity of the shrine and have rites conducted continuously. By maintaining the shrine in good condition and preserving its purity, the kami could exercise its power, pollution could be avoided, and if by chance one were to become polluted, the polluted location would be excised, and the grave response of ceasing rites could be carried out. Because it was thought divine authority was reduced when uncanny events and disasters occurred or the main shrine building was damaged, it was necessary to repair and rebuild the main shrine building and keep it in a pure state. The main shrine building at Ise Jingu was completely rebuilt and transferred (sengu) "once every twenty years" (shikinen) as a national project, but if the main shrine building was damaged in the interim, the divine spirit was transferred to a temporary shrine, and when the main shrine building was repaired, the divine spirit was returned. Thus a temporary-shrine transfer was employed as a measure to cope with the problem. The appearance of frequent use of temporary-shrine transfers in the medieval period was not due to a rise in sense of reverence, nor more frequent disasters, nor a decline in the level of technical skills needed to transfer the shrine, nor the impossibility of obtaining suitable materials, but was most likely due instead to an increasing consciousness of the uncanny and of pollution as well as a rising consciousness of the necessity of preserving the purity of the shrine precincts and maintaining the shrine itself in a proper state. Comparing the number of uncanny events that occurred at Ise Jingu with the number at other shrines, it is clear that the number at Ise, along with that of such events at Iwashimizu Hachimangu, was particularly high, which was a result of the fact that the two shrines were sobyo, mausoleums for imperial ancestors, who protected the nation Then, a special characteristic of the uncanny events at Ise Jingu was that damage to the main shrine building was considered an uncanny event and reported to the state. The replacement of the shrine was ultimately the responsibility of the state, and it differed from other shrines in this respect, and thus damage to the shrine building was treated as an uncanny event and immediately reported to the state. However, in the latter half of the Muromachi period, even if there was a report of uncanny events, the response of an immediate transfer to a temporary shrine could not be carried out due to the paucity of state funds. I have clarified above that disasters were not natural phenomena but divine will during the medieval period, and that it was though necessary to fathom the divine intentions in order to placate them and prevent additional crises. Further, I surmise that as Ise Jingu was a core institution capable of detecting uncanny events of national consequence, in the case of damage to the main shrine building, there was a need to maintain the shrine in proper condition by employing a temporary-shrine transfer as was used in the regular shikinen sengu.