This paper argues that Theodore Beza shaped the trinitarian language of the Belgic Confession (1561), integrating scholastic precision into the Reformed confessional framework. Early Reformed theologians embraced a type of trinitarian minimalism, favoring biblical and creedal language over philosophical elaboration. However, polemical pressure in the latter half of the sixteenth century necessitated greater clarity. This shift toward theological precision is evidenced in Beza’s Confession (1559) and Theses on the Trinity (1565), where he described the divine persons as really, truly, and eternally distinct. Drawing on medieval terminology, Beza’s mild scholasticism marked a departure from earlier trinitarian minimalism. Through comparative analysis, this study demonstrates that the Belgic Confession adopted Beza’s trinitarian distinctions verbatim. This is accomplished first by explaining Beza’s use of scholastic distinctions in context. Then, building on the work of Nicolaas H. Gootjes, the known sources of the Belgic Confession are compared to show that the particular distinctions of the confession originated solely with Beza. While scholars have confirmed Beza’s influence on various portions of the confession, this precise point remains untouched in the secondary literature. Thus, this short study demonstrates that Beza’s influence on the confession is greater than previously proven. This conclusion highlights Beza’s role in developing the Reformed tradition through its confessional documents—unifying Reformed trinitarianism with scholastic precision.