The Kyokushin Dojo Kun (Training Hall Oath) was written by Mas Oyama with the help of Eiji Yoshikawa, the author of the novel Musashi, which was based on the life and exploits of Miyamoto Musashi, Japan's most famous Samurai warrior.
The Dojo Kun is usually recited at the end of each training session, when the students and instructors are lined up by rank in Seiza (formal kneeling). Each line of the Dojo Kun is recited by the most senior student and repeated by the entire class together. Some dojos choose not to recite the Dojo Kun for various reasons.
Some dojos recite the fifth line as "We will follow our Gods and Buddha...", which is a more literal translation of Shinbutsu. However, the full meaning of the Japanese word is not expressed in this literal translation, since it involves Buddhist and Shinto principles with which many Westerners are not familiar. Other dojos recite the line as "We will follow our religious principles..."