The aim of this article is to examine the dichotomy between “Hussite” and “Catholic” through the lens of how sinfulness was perceived by the Hussites (Czech Utraquists) and their military and political Catholic opponents. The study focuses on the unique perception of sinfulness as a distinctive feature of Hussite ideology compared to anti-Hussite views. The sources used include theological and polemical writings of Hussites such as Jan Želivský, Mikuláš of Pelhřimov, and Petr Helčický, as well as their ideological predecessor Jan Hus. Additionally, the study examines the Hussite program known as the “Four Articles of Prague” in its various forms, which were supported by both the radical Taborites and the more moderate Prague Hussites. Traditional Catholic theological criticism, notably from figures like Ferdinand of Lucca and Gilles Charlier, and other sources reconstructing fifteenth-century Catholic norms and perceptions, particularly in Hungary, are also considered. The analysis identifies two key features of the perception of sinfulness in Hussite ideology: sin as a social offense, and the belief that all people are equal in front of sin, implying that a ruler’s sin justifi es disobedience, including armed resistance. The author concludes that the dichotomy between “Hussite” and “Catholic” is only partially evident in this context. Gilles Charlier, a Catholic theologian, considered only those sins that directly harmed the state and society (e.g., theft , murder) as social crimes, while he did not classify “simple fornication” as such a crime. In contrast, fornication among the Catholic opponents of the Hussites, particularly in fifteenth-century Hungary, continued to be regarded as a suppressible social offense under the laws established by Saint Stephen (997–1038). Charlier advocated for tolerance towards the sins of monarchs and infl uential individuals to avoid severe unrest. The Hungarian kingdom in the fifteenth century retained the legal right for the estates to resist the monarch if he violated the Golden Bull of 1222. This conclusion, highlighting the similarities between the views of the Hussites and their opponents, is unprecedented in historiography. While R. Novotný noted the similarity between the estates of the Hungarian and Czech kingdoms, the recognition of these ideological parallels is a new contribution.