This article discusses Tolstoy’s faith in the unity of its two aspects: as the state of mind of its carrier and in terms of its content and the life principles that flow from it. It is shown that at the same time and in the same respect Tolstoy was the bearer of the faith and its investigator; therefore, its adequate interpretation is possible only if the principles established by him for himself are taken into account instead of an abstract and outward interpretation of what faith should be. The article considers, first, Tolstoy’s explanation of faith in various works, letters, diaries, and the like during the last thirty years of his life; and second, his distinctive expressions of faith along with discussions of it. The article demonstrates the equivalence of Tolstoy’s state of mind and the content of his faith, as well as its purely individual character. The study concludes with a discussion of the significance of Tolstoy’s understanding of faith for us today.