The article discusses Tolstoy’s faith in the unity of its two sides: as the state of mind of its carrier, and in terms of its content and life principles that flow from it. It is shown that at the same time and in the same respect Tolstoy was the bearer of a 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 abstract and outward interpretation of what faith should be. The article considers Tolstoy’s expression of the essence of his faith in numerous works, letters, diaries, etc. during the last thirty years of his life. The article shows the equivalence of Tolstoy’s state of mind and the content of his faith, as well as its purely individual character. The conclusion is made about the significance of Tolstoy’s understanding of faith for us today.