Luther’s method of theology is that of Scriptural interpretation. Erasmus complains that Scripture is obscure, an authoritative tradition is needed to interpret it. Luther confirms both the external and internal clarity of Scripture itself: “External clarity” is guaranteed by the public proclamation of God’s word; the natural meaning of the “text published to the entire world” is found in the very letter of Scripture. “Internal clarity” guarantees that the same Holy Spirit who inspired the canonical authors “internally moves” the hearer of the word granting him/her participation in Christological grace. The Spirit-inspired word is an efficient carrier of Trinitarian grace that changes its hearers. In contrast to the skeptical view of Erasmus, Luther uses the assertive propositions of Scripture as a means of assuring theocentric salvation. Because of its double clarity, “Scripture alone,” sola Scriptura, is a sufficient norm for the truth of the gospel. Another central feature of Luther’s theological method in The Bondage of the Will is his view of the conflict between the opposing transcendental powers which fight over the control of the human beings: the Triune God’s goodness, love, and grace against unfaith, sin, and Satan. Only God’s Spirit can liberate the sinner from captivity by unfaith and evil. Erasmusnever mentions God’s Spirit when discussing grace, and there is no mention of Satan in his treatise. Moreover, the distinction between the “things below oneself” and the “things above oneself” is crucial for Luther’s understanding of law and gospel; Erasmus makes no distinction between the two realms.