This article examines legal certainty as a constitutional requirement relating to the content and quality of law. It argues that, in constitutional law, this category is not limited to the clarity of the verbal formulation of a legal norm, but also encompasses the systemic coherence of legal regulation, the foreseeability of legal consequences, the consistency of law enforcement, and the inadmissibility of unlimited discretion on the part of public authorities. The article shows that legal certainty is of particular importance in the spheres of property and entrepreneurial rights, since it is precisely in these areas that a person must be able to assess in advance the legal consequences of their actions, the limits of state interference, and the conditions for preserving an acquired legal status. It concludes that the constitutional standard of legal certainty includes three interrelated elements: the comprehensibility of the normative prescription, the calculability of its consequences, and the procedural consistency of decisions made by public authorities.