While the Nicene confession of the Son’s consubstantiality with the Father was foundational for the Reformers, the metaphysical architecture underlying Nicene orthodoxy—particularly as mediated through Augustine—elicited both appropriation and reconfiguration. This paper investigates how two key Reformed theologians, John Calvin and Francis Turretin, retrieved Augustine’s articulation of divine simplicity within his Trinitarian theology, not as passive receivers but as discerning theological interpreters shaped by Scripture and polemical context. The paper centers on a close reading of Augustine’s De Trinitate (especially Books V–VII), where he grounds his Trinitarian logic in the indivisibility and simplicity of the divine essence, even as he distinguishes the persons according to eternal relations. Sample key passages from De Trinitate that will be discussed in relation to Calvin’s and Turretin’s include V.6.7 and VI.4.6, which both defends the Son’s God-essence. The second section analyzes how early Reformed theologians such as John Calvin and Francis Turretin engaged Augustine’s Trinitarian theology, especially the doctrine of simplicity (simplicitas Dei). Calvin’s Institutes of the Christian Religion I.xiii, along with relevant commentaries (e.g., his exegesis of John 1:1 and Colossians 1:15), will be examined for how he affirms the divine essence and relations using Augustinian categories, albeit with a more restrained metaphysical register. Turretin’s Institutio Theologiae Elencticae (I, qu. 8, 10, 12, III, qu. 3,4, 5, 6, 7, 23, 24) provides a scholastic Reformed synthesis, articulating divine simplicity with reference to both Augustine and the Nicene tradition. Apart from arguing from primary sources, this paper will be interacting with Duby’s thesis on Divine Simplicity: A Dogmatic Account. While he rightly points out that according to Turretin, “Some [divine] attributes (immensity, eternity, and others) are strictly incommunicable, and in these there is ‘nothing similar or analogous, or no image and vestige in creatures’. Others are communicable, not essentially or formally, but ‘analogically’…”, he could have further argues that to be like Christ for the reformers has a solid philosophical-Augustinian tradition of the incarnate Christ being the Son-God who is and has divine essence that embodies these two sides of communicability, and protestant Christians nowadays can benefit from this argument to grow towards divine goodness because of the virtue categorization and accessibility. In view of this gap, the final section considers how this Reformed retrieval of Augustine’s Trinitarianism—especially its fidelity to Nicene categories—can inform contemporary evangelical theology. I will focus on two aspects: The incarnation of Christ the Son God and the divine virtues which is God in essence to this world. The retrieval of divine simplicity today must contend with modern critiques of metaphysics, yet the Reformers’ selective but serious engagement with Augustine offers a model for theological retrieval that is both historically grounded and doctrinally constructive. n sum, this paper argues that early Reformed theology did not bypass the Nicene metaphysical heritage but critically retrieved Augustine’s account of divine simplicity as a central element of Trinitarian orthodoxy. Their engagement demonstrates the Reformers’ commitment to a catholic theology that upheld the enduring legacy of Nicaea through the lens of biblical fidelity and doctrinal clarity; in particular, the reformers inherit and defend Christ as the Son-God to argue for a firm hold of Christ as the Son-God and His virtues for Christians to follow, not only in the Reformation world but in ours as well.