The book “Optina Pustyn and Its Time” was written by the famous writer and theologian of the Russian diaspora, Ivan Mikhailovich Kontsevich (1893-1965). The introductory chapters reveal the concept of eldership and trace its history in Russia in the 18th-19th centuries. The author pays special attention to the life and exploits of the venerable elders of Optina. The book contains their letters and teachings, precious memories of contemporaries and spiritual children, among whom was I. M. Kontsevich himself. His book is interesting, informative and instructive to this day and is in great demand among readers. Realizing how beneficial reading it is for any Orthodox believer, we are republishing this work, providing it with the necessary notes and a name index.