Abstract : Among the most debated questions of today's historiography, comparison is increasingly relevant. This is mainly due to the impact it has on fields of study as different as anthropology, law, religion, history, etc., and the extremely variegated articulation to which it gives rise between them. In my paper, I will concentrate on the ambit of normative history and consider the case of Alberico Gentili (†1608). With respect to Gentili, comparison helps us trace the role of theology and religious ideas in early-modern legal debates on prince and sovereignty. Special attention will be given to the distinction between God’s absolute and ordered power (potentia Dei absoluta and ordinata) and to Gentili’s image of Luther.