Shinto

Salt and Shinto

In short, in shinto, salt is used to purify.

Left outside of houses in little pile of "mori shio" (piled up salt) generally to the right of the door (left maybe okay too?) so that people who pass through the door are purified. People that come back from a funeral use this salt or other salt to purify themselves by scattering salt upon their body.

Some say that the origin of mori-shio piles outside restaurants was to encourage the arrival of rich and noble customers such as a "daimyo," who would come on horseback since horse love salt. Another more probable theory is that this originates in a Chinese story that an emperor who had
many wives would visit them by turns. To encourage the emperor to visit one of the wives spread salt out side her house, which the cows pulling the emperors carriage stopped to lick, forcing the emperor to stay at that particular house. Either way, it is said that should a rich or noble customer arrive at the restaurant then the owner should scatter the mori-shio, as if eaten by a horse or cow,
to signify that an important customer is inside. http://www.so-net.ne.jp/copainterior/moriSio.html

Maki-shio (scattered salt) will be scattered around the boundary of a house on the first day of the month so that impurities do not enter the house.

Mori-shio may be put at the four corners of a plot of a land to purify that area, especially when one moves in.
http://katsuma.net/move/fuusui.html

Salt will be scattered on the ground in the pacifying the spirits of the land ceremony held on the empty plot before buildings are erected. See
http://www42.tok2.com/home/leftyyas/new_page_130.htm

Salt is also scattered in quantity by sumo wrestlers before each bought to purify themselves and the sumo ring ( "dohyou") which is considered to be a sacred place (women are not allowed to enter it because they are considered to be impure. One young female wrestler who won a regional school sumo competition for primary school children was not allowed to go and collect her prize in the ring from a famous sumo wrestler for this reason ). Here is a primary school children’s sumo contests showing a teacher scattering salt in the first picture.
http://www.biwa.ne.jp/~okinaga/gakkou/syasin/14syasinn/14syasinn4.htm

This page claims that sumo wrestlers scatter the salt also because it helps to kill germs that might otherwise infect cuts and that 45 kilos are scattered every day at the national sumo tournaments. The crowd seems to like it when a wrestler scatters a lot of salt since such action is often met with a cheer.
http://www.ktv.co.jp/ARUARU/search/arusio/shio5.htm

This page shows a sort of joke on the idea that salt is necessary to purify people after a funeral, with a sumo wrestler scattering salt on people wearing black and grey. The title of the page is "Funerals are not scary" and the suggestion is that scattering salt is an unnecessary superstition.
http://www.stoneplaza.co.jp/kuyou/funeral/fu06.html

White things (such as salt) are considered pure. So all the utensils (pots) and the things
that are generally offered on the household altar (kamidana) are salt, rice, water, rice wine
and sometimes strips of paper are usually white or transparent. Red and blood are the signs of
impurity but red and white are the colours of celebration.

Salt is also an offering made to the spirits (kami) on the household altar in a little dish (again
in a little conical pile) and at shrines again in piles, sometimes enormous conical piles
http://kasuichi.gooside.com/photo/01_allJapan_b.html
and sometimes even in bags of household salt.

In Shinto mythology we are told that the first land mass Onogoro Shima, (self-congealing island) was formed when the salt separated from the brine when Izanagi(-nomikoto) stirred it up with his jewelled lance.

Salt is very popular in Japanese culture. A great deal of Japanese food is salt, especially shoyu (soy sauce) and miso (curdled soya bean paste) which is eaten at almost every traditional meal. There are also salt saunas were people rub salt on themselves as they sweat to make themselves sweat more and to purify the skin.