The Asceticon ("ascetic discourses") by Abba Isaiah of Scetis is a diverse anthology of essays by an Egyptian Christian monk who left Scetis around 450 AD.
Originally composed in Greek, the Asceticon consists of 30 essays ("logos" in singular, "logoi" in plural) on subjects including: advice for novice monks; precepts for those who have renounced the world; sayings and stories by Abba Isaiah; various letters, sermons, and sayings.
Logos 30 includes several sayings that were also included in the Apophthegmata Patrum (Sayings of the Desert Fathers), but in a different form, giving scholars some evidence on how those sayings evolved into their final form in the Apophthegmata Patrum.
Abba Isaiah was also influential in bringing Christianity to Palestine.
A Sogdian fragment of the 4th discourse, translated from Syriac, was found in MC C2, along with part of a commentary on the 15th discourse by Dadisho Qatraya.