The language of theological principles signals the dependence human reason maintains on the gifts of the Triune God for any knowledge of God. The seventeenth-century divine Johannes Wollebius prods us toward a distinction: “The principle of the being of theology is God; the principle by which it is known is the Word of God.” That is, the ontological principle of all such knowledge is God himself, the only one who possesses this knowledge. God’s overflowing wisdom comes to humans in two forms. “The Church is creatura verbi divini: the creature of the divine Word. The Church is constituted by God’s action and not by any human action. . . . And the way in which the Church is constituted by divine action determines the character and scope of human action in the Church.” The church’s life and knowledge are enjoyed in a creaturely manner determined — in both character and scope — by their dependence on the divine Word. The Word’s activity takes two forms: external and internal.

The external principle is a person, the incarnate Son of God. . . . The internal principle is the pledged Spirit, who illumines the Word and not only enables but also actualizes reception of that Word in the minds of God’s people.

“Knowledge of God” by Michael Allen in Christian Dogmatics: Reformed Theology for the Church Catholic, edited by Michael Allen, and Scott R. Swain (Grand Rapids: Baker Academic, 2016), 20-21.