Currently, twenty-five documents are confirmed as containing Keizan Jōkin’s 瑩山紹瑾 biographical data. In these documents, how Jōkin received his enlightenment encounter under Tettsū Gikai’s 徹通義介 instruction are described differently, and can be classified in three ways: 1. As through the kōan byōjōshin-ze-dō (平常心是道; sixteen documents); 2. As through the Lotus Sūtra (four documents); 3. As through monshōgodō (聞声悟道; one document). In another four documents, the way to certify enlightenment is not mentioned.
Since Dharma Transmission is only held once between master and apprentice, it is unnatural that multiple examples of the encounter exist.
In fact, all the documents of type 1 in which an encounter is mentioned were created in modern times. By taking notice of the documents composed in earlier ages, namely the Tōkokuki 洞谷記 which incorporates Jōkin’s biographical data and the Busso-shōdenki 仏祖正伝記 composed in 1399, although the Dharma Transmission encounter is not clearly described, in the Busso-shōdenki an encounter of type 2 is described. Therefore, we may conclude that an encounter of type 2 best reflects the actual historical situation. Moreover, an encounter of type 2 corresponds to Jōkin’s enlightenment encounter recorded in the Shōbōgenzō-Bussogosoku 正法眼蔵仏祖悟則 composed between 1366–1399. As far as we can tell by looking at the content of documents composed not long after Jōkin’s death, we find that Jōkin’s enlightenment encounter is strongly suggested as having been of type 2.
