More from chapter five.
Luther's emphasis on the battle with Satan ultimately being a battle of two words (God and Satan's) is in many respects a novel understanding of the activity of Satan in the history Christian thought. Although the Patristic theologians rightly took the Devil very seriously, they did not comprehend the real source of Satan's power in his corruption of and opposition to the Word. For many of the Church Fathers (particularly those we examined above), the Devil was a malevolent force to be overpowered (Irenaeus, Athanasius) or tricked (Origen, Gregory of Nyssa, etc.) by a still more powerful or crafty supreme deity. Despite the element of biblical truth in their accounts, this often led to their descriptions of the work of Christ to become grotesquely mythological. Similarly, many theories of penal satisfaction (at least as we have observed them in Anselm) make the Devil the catalyst of the need for satisfaction, but little more. The defeat of the Devil sideshow to the main event of satisfaction. Hence, there is often a lack of emphasis on Christ ratification of his testament through his death and resurrection, and its significance for the defeat of the Devil. Lastly, theories of moral influence have moved even farther away from the biblical concept of Satan. For this group of thinkers, bondage to the Devil eliminates the possibility of moral influence, because an enslaved person cannot be influenced to change their state of bondage. As a result, the concept of Satan becomes either superfluous or detrimental to human moral agency.
In Luther we find that the nature of the Devil and his false mediation become properly defined. For the Reformer, God is not only opposes the Devil, but the Devil also functions as a mask of God’s own wrath. This is the case because the "the whole creation is a face or mask of God." Satan distorts the Word of God and holds humans in his bondage. Human belief in Satan's false word incurs God's wrath, while bondage to Satan is a manifestation of this very same wrath. There is a great deal of biblical support for the view that Satan's power comes from his ability to rule over humans because of their sin. He is often pictured as an accuser in the heavenly court (Jb 1:6-8, 2:1-7; Zech. 3:1-10; Rev. 12:10). In fact, the word "Satan" can mean "adversary" or even "accuser" in the original Hebrew. In effect, the Bible pictures Satan as God's enemy who nonetheless maintains his power because of God's wrath against sin.
Standing in Luther's tradition, we may say that although God is just and faithful, unbelief in his graciousness only becomes reinforced in sinful humans because they perceive his law and wrath (Rom 1:18-32) and as a result stand in self-justifying opposition to it (6:7-25). Because of this humans only become more and more ensnared in the power of Satan's false word, because they perceive God in his wrath as untrustworthy. Therefore, God’s war against the Devil is both a war against his own activity as wrath, as well as human unbelief. Fulfilling the law, Christ's Word of the gospel undoes God's own wrath and therefore his permissive will to allow the Devil to function as the "god of this world" (2 Cor 4:4). This is why Jesus' healing miracles and exorcisms (i.e. acts of opposition to the manifestations of the reign of Satan) are always preceded by the forgiveness of sins. Through the forgiveness of sins, God both defeats the power of Satan and overcomes human unbelief. God does not wish to have a wrathful relationship with humanity, but rather one of grace and self-donation, wherein humans assume the role of receivers of all his goodness. By defeating the Devil, God in Christ reestablishes himself as a gracious giver and humans as grateful receivers of his goodness.
This view of the history of salvation as a mirabile duellum between the word of Christ's grace and the power of Satan is dramatized well in Luther's most famous hymn A Mighty Fortress is Our God (1527/1528?). The hymn pictures the Devil overpowering God’s creation: “The old knavish foe/He means earnest now/ Force and cunning slay His horrid policy/ On earth there's nothing like him.” In order to prevail, Christ must utterly donate himself to human beings by entering into the battlefield of creation himself: “Ask'st though who is this?/ Jesus Christ it is/Lord of Host alone,/ And God but him is none/ So he must win the battle.” How does Luther describe Satan's defeat? He does not describe the crucifixion and resurrection, as he does in other hymns such as Dear Christians One and All Rejoice or Christ Jesus Lay in Death's Strong Bands. Rather, without excluding the work of sacrificial atonement as a necessary basis, he emphasizes in this hymn Christ's prophetic Word of grace as the thing that ultimately undoes Satan: “Let him [Satan] rage his worst/ No hurt brings about/ His doom it is gone out/ One word can overturn him./ The word they shall allow to stand.” God's omnipotent Word of grace cannot be overturned. It is the very thing that overthrows the Devil's rule. Indeed, even if "the world with devils swarm” and take “life/ Wealth, name, child and wife” the divine promise of grace cannot be abrogated. God by his omnipotent Word has promised believers the kingdom of his glory: “Let everything go/ They have no profit so/ The kingdom ours remaineth.” In the end, all Christians are heirs of the kingdom and become "lords of all." They thereby reestablished in their proper role as receivers of all of God's goodness. In the same manner, God reestablishes his relationship with humans as one of self-donation by entering into the field of battle with Satan.