In the XV and XVI centuries, the idea of great power that Russia was increasingly often attributing to itself had its roots in theology. As follows from contemporary literary sources and diplomatic correspondence, the labels velikaya derzhava (great power) and velikoye tsarstvo (great kingdom) attached to the Russian polity were supposed to emphasize that the power of Russian princes continued to be interpreted as divinely instituted in opposition to some European rules, who, in the eyes of Russian political elite, may have preserved their power, but lost greatness. That greatness was not understood as something established through competition and recognition in the international system. Neither had it reflected some peculiar greatness of the Russian tsar as a person. Rather this greatness was about the quality and the history of domestic regime. However, one and a half centuries hence, one could identify two clear shifts in the Russian discourse on greatness. Firstly, the great power discourse, remaining firmly associated with the theocratic origin of Russian supreme power, transformed almost entirely into a bulk of panegyric poetry and sermons glorifying the monarch himself and comparing him to a living deity. Russia was thought to be great only insofar as it had undergone a fundamental metamorphosis and had been made great by Peter the Great. Secondly, the greatness of political power soldered entirely with the undivided and unaccountable manner of its application, i.e. with Russian autocratic regime. I argue that the abovementioned shifts may have been conditioned by two interrelated processes: the monarch’s assumption of the role of the head of the church, and the creative appropriation of Byzantine political culture with simultaneous Europeanization of Russian lifestyle.