The book is dedicated to the study and reconstruction of Slavic ideas about the world and the Universe. The authors are convinced that the peculiarities of worldview laid down at the dawn of the history of the Slavs continue, to one degree or another, to remain relevant today. Understanding the archaic layers of traditional culture only allows us to comprehend it in its entirety and diversity, to trace the ways of interaction between peoples. In addition to folklore material, the book widely uses a variety of data from the field of history and comparative historical mythology of the peoples of the Indo-European cultural and linguistic community. The authors pay special attention to the intersection of Christian and pagan ideas that developed during the Christianization of the Rus and Slavs tribe and the subsequent period of dual faith.