Legal provisions regarding blasphemy and religion-related expression in Indonesia underwent a significant transition after Article 156a(a) of the old Criminal Code was replaced by Article 300 of the National Criminal Code. This study examines how that transition has altered the relationship between the protection of religion, religious authorities, and freedom of expression in Indonesia. The study employs a normative legal methodology, using both statutory and case-law approaches, through analysis of legislation, Constitutional Court decisions, a number of blasphemy cases, and relevant scholarly literature. The legal materials were analyzed using the principles of legality, legitimate purpose, necessity, and proportionality as reflected in the Siracusa Principles, while also taking into account international human rights standards regarding religious expression. The research findings indicate that the application of Article 156a(a) of the old Criminal Code relied heavily on judicial interpretation and religious authority in determining whether a particular expression could be categorized as blasphemy, thereby rendering the boundary between protected expression and criminal acts uncertain. Article 300 of the National Criminal Code marks a significant normative shift by shifting the focus of criminal protection from religion as an abstract object toward the protection of individuals, groups, or communities from hostility, hatred, violence, or discrimination based on religion or belief, and by explicitly exempting certain forms of objective, community-specific, and scientific expression from criminal liability. Nevertheless, the use of concepts that remain open to interpretation suggests that the effectiveness of the new framework will depend heavily on future judicial interpretations. This study contributes to the field of religion and law by demonstrating how criminal law reform reconfigures the relationship between religious authorities, state regulation, and freedom of expression, while also offering a framework for assessing whether the new regime can avoid the interpretive uncertainties present in the previous blasphemy laws.