As a painter, Roerich is usually grouped with the Russian Symbolists. His best-known paintings (generally tempera on canvas or cardboard) feature old Russian churches, Himalayan landscapes, or religious scenes representing various Eastern religions. He also painted the interiors of several churches, as well as the backdrops for a number of operas, including the premier of Stravinsky's ''Sacre du printemps.'' Museums of his artwork exist in New York City, Moscow, and Naggar (Himanchal Pradesh, India), among other places.
The Roerichs joined the Theosophical Society in 1920, Nikolai having been exposed to Buddhism through working on a Tibeto-Mongolian temple in
[[Saint Petersburg ]]. As a worldwide schism developed among Theosophists over the claims of Annie Besant and the young Krishnamurti, the Roerichs began receiving their own revelations from the Master "M" (for "Morya") of Theosophical lore. "M" is said to represent a certain Brotherhood of Adepts headquartered in the Himalayas, whose members assist with the process of spiritual evolution.
"M's" revelations (in Russian) became the series of seventeen Agni Yoga books, also known as the Teaching of Living Ethics (Zhivaya etika, Живая этика). These stress the perception and development of unseen spiritual potencies. Later volumes claimed a cosmic significance for Helena (called the "Mother of Agni Yoga") as world savioress.