The Rule of Joseph Volotsky (1439–1515) was known to his first biographers of the 19th century, P.S. Kazansky, N.A. Bulgakov and I. Khrushchov. All of them worked with the Rule incorporated in the Great Menaion Reader by Metropolitan Macarius of Moscow and All Russia. Ya.S. Lur’e at 1950th discovered a different version of the Rule, the brief one, which consists of 11 Discourses, and several collections with an incomplete set of Discourses and potential Discourse 12. The brief version was published by Ya.S. Lur’e together with potential Discourse 12 in 1959. He characterized the manuscript tradition of the Rule as very stable in contrast to another work, the Enlightener. The author of the article found the manuscript in OR GIM (Manuscript Department of the State Historical Museum), Diocesan Collection, N 248. It is indicated as Discourse 12 of the Enlightener in the description, but, after having examined the manuscript, the author identifi ed this text as fragments of Joseph Volotsky’s Rule, which can be dated to the late 15th century, and thus it is a lifetime fragments of the Rule. The verification of the versions helps to establish that the first fragment is Discourse 11 of the Extended Rule. It is followed by the previously unknown Discourse 12, which is very much alike with Discourse 13 of the Menaion version. It is followed by Discourses 2 and 3 of the Brief Rule, and by a substantially shortened text of Discourse 13. The author concludes that originally the Brief Rule may have contained 13 instead of 11 Discourses. At the same time the Brief Rule consists of two “wills”, and the second one contains Discourses 12–14. Ya.S. Lur’e established that much of their content duplicates the first 11 Discourses. In the Moskovskiye tserkovnyye vedomosti the auther found a note with references to the lost manuscript N 482 from the Volokolamsk Monastery, which could contain only the “second” will without the first. He concludes that the Menaion redaction could originally contain 11 Discourses instead of 14, and the merging of the two wills occurred after the death of Joseph Volotsky