Concerning the relationship between the Kukai sozuden and the Yuigo nijugokajo, many have assumed that the Goyuigo was written on the basis of the earlier Sozuden. Nishida Nagao alone among them has said that the Sozuden was a revision of the Goyuigo. I also believe that the Kukai sozuden is the product of the second half of the tenth century or later based on the admonitions given in that text dated on the last day of the fifth month of 834. I created a list comparing the sections of both texts and explored their chronological relationship. As a result, from (1) a comparison of the extremely long sections of the Yuigo nijugokajo, (2) the use of the term Daishi, and (3) the rich details of the description of Kuka's last days, I reached the conclusion that Kukai sozuden is a revision of Yuigo nijugokajo.
