The biography of Hieromonk Nikon (1888–1931) consists of the following parts: his diary, which he wrote when he entered Optina Pustyn for three years (from 1907 to 1910), and the memories of his spiritual children about him . Recordings of some of his sermons have also survived. He died still very young in exile in 1931 from tuberculosis. The entire short life of Fr. Hieromonk Nikon is imbued with deep faith in God and unshakable devotion to His will under all difficult circumstances: in the monastery, in prison, and in exile - and is so instructive that we considered it necessary to collect the available information about him (far from complete) that makes up this biography.