About Nittai-ji

Kakuōzan Nittai-ji is a Buddhist temple located in the city of Nagoya, Aichi prefecture, Japan. It was built in 1904 in order to keep the ashes of Buddha, given to Japan by the Kingdom of Thailand. ”覚王” literally means "Enlightenment King," referring to the Buddha, and “日泰” means Japan and the Kingdom of Thailand in Japanese.
Relics of buddha from the Supreme Patriarch of Thailand

Buddhist relics – The ashes of spiritual Masters

Śarīra is a generic term referring to Buddhist relics, although in common usage it usually refers to pearl or crystal-like bead-shaped objects that are purportedly found among the cremated ashes of Buddhist spiritual masters. Relics of the Buddha after cremation are termed dhātu in the Mahaparinibbana Sutta. Śarīra are held to emanate or incite 'blessings' and 'grace' within the mindstream and experience of those connected to them. Sarira are also believed to ward off evil .