Mission is one of the main tasks of the Church. The missionary activity of the Russian Church of the pre-revolutionary years is assessed in different ways. Was the church people aware of the changes taking place in the life of the country, which ultimately led to the catastrophe of 1917? Did the preachers try to master the language that the Russian intelligentsia is used to hearing? Was the activity of Orthodox missionaries effective? A.G. Kravetsky considers missionary discussions, the period of preparation for the All-Russian Church Council 1917-1918. and documents of the Council itself.