In 1825, a travelling opera company from China came to the southern islands of Thailand to perform for chinese tin mine workers. Mysteriously the company fell ill and grew sick. They embraced an old ritual of a strict vegetarian diet in honor of the two emperor gods, Kiew Ong Tai Teh and Yok Ong Sone. Performing ritual ceremonies, specially ordained devotees called Mah Song , became the spirit horse for the Gods to manifest into the human realm. Harnessing supernatural powers, the Mah Song performed sacred rites of self-flagellation, such as body piercing to shift evil from other individuals onto themselves and in doing so purifying the community of its sins. Amazed by the self sacrifice and the quick recovery of the travelling Opera Company, the local people embraced this miracle of faith and belief still to this day. Under the full moon of the ninth house, people celebrate the ritual cleansing of sins by the Mah Song spirit horse.