The other day I visited Samukawa Jinja (寒川神社). This was work-related, so I will probably write more about that in the future, but today I want to talk about the jinja itself, because it is interesting for several reasons.
First, it may well offer more formal prayers for adherents than any other jinja in Japan. No-one collects formal statistics on this, but a priest I spoke to who has served at both Samukawa Jinja and Meiji Jingū estimated that Samukawa does about ten times as many. They accept requests for prayers from people who cannot get to the jinja in person, and a lot of people take advantage of this. In principle, this is open to people living outside Japan as well, but you would have to transfer money directly to a Japanese bank, and write to them with the request, so it might not be terribly practical.
The jinja was historically important as well. It was the Ichinomiya of Sagami Province (most of modern Kanagawa Prefecture, although the bit I live in was part of Musashi Province), and there are a number of important matsuri, with long histories. Its location is now in a small community, served by a station on a minor local line (the JR Sagami Line), one that runs perpendicular to the main commuter routes into Tokyo. The area may have been more important in the past, but today the jinja is the only significant institution there.
In terms of practice, the jinja is particularly known for “Purification of the Eight Directions” (Happōyokë, 八方除), which is a ceremony to remove all ill-fortune, whether from the place you live, the way your home is set up, inauspicious days, or unlucky directions. It is said to reduce misfortune in severity, and make good fortune as great as possible. This ceremony is also said to be unique to this jinja. It does seem to be universally applicable, which may be part of the reason for its popularity.
The kami of the jinja are known as Samukawa Daimyōjin (寒川大明神), and individually as Samukawahiko-no-mikoto (寒川比古命, male) and Samukawahimë-no-mikoto (寒川比女命, female). That sentence includes everything that is known about these kami. I was talking to the priests, and they said that there are no myths about the kami; the earliest records simply note them as “Samukawa no kami”, or similar. These are not really even names — they just mean “the male and female kami at Samukawa”. To the best of my knowledge, they are not enshrined at any other jinja (but I forgot to ask the priests explicitly).
The only thing that the many, many people who venerate the kami of Samukawa Jinja know about them is that they are enshrined at that jinja. And that is enough. This is a particularly pure and clear example of the fact that reverence for and attachment to a particular jinja need not involve any knowledge of the kami, because in this case there is nothing available to know. This is equally true of a lot of people who are attached to jinja with kami about whom we know rather more. It is why there can be disagreement or ambiguity over which kami is enshrined at a jinja without it making any difference to the practice of people who visit. Of course, sometimes the identity of the kami does matter — it matters that Amaterasu Ōmikami is one of the kami enshrined in Isë Jingū, but even there the identities of some of the kami enshrined in the Outer Sanctuary are unknown.
Samukawa Jinja, then, is a bit out of the way in an average part of Kanagawa, has its own special ceremony, and venerates kami about whom nothing more is known. It is very rarely mentioned in studies of Shinto, because it does not fit into any larger narratives. You only write about Samukawa Jinja if you want to write about Samukawa Jinja itself. (Case in point: this blog post.)
On the other hand, it does illustrate, very well, an important feature of Shinto. It does not matter if Shinto practice fails to fit any larger narrative. All that matters is the practice at this jinja, with these kami.