Post-secularism is the fundamental evidence of the end of modernity. Modernity, as sleeping reason in Francisco Goya's painting, realizes that, although it thought that it was awake, it was producing monsters. We try to analyze post-secular philosophy from the point of view of Russian religious thought. We believe that such philosophers as Vladimir Soloviev, Pavel Florensky, Sergey Bulgakov, Nikolai Berdyaev, Georges Florovsky, and Semen Frank may be helpful for understanding and overcoming post-secular order. Their unique views on the relations between religion and philosophy, science, and social life are apparently missing in the current Western debates. It seems to us that Russian religious philosophy becomes surprisingly up-to-date and attractive in the contemporary world. We hope that the present volume will be a significant step forward in the inclusion of the heritage of Russian religious philosophy in contemporary debates.