Theologians of glory searched for God everywhere except the Cross of Christ.
In his exposition of the Magnificat of Mary, Luther distinguished between death and life, hiddenness and revelation, sin and salvation, sign and deed at the only place where such a distinction can accurately be made: at the Cross. He was compelled to make the distinction in order to express the reality of the Cross which killed and made new in fact, not merely substantively as a sign. For Luther, the Old Adam died and the reality of this death was not an endless projection into the future but the reality of the Cross. The Cross marked sinners, not as mud covers a pearl, but in the relationship of Christ to sinners, in the justification of the Old Adam by Christ’s own sin, execration and death. For Luther Christ’s death and resurrection was the justification of sinners. The Cross brought death upon the Old Adam to end the relationship he has with God according to His wrath. Jesus’ resurrection from the dead simultaneously heralded a new relationship with God according to His steadfast love and mercy. This was where Luther made the eschatological break with late-medieval ways of explaining Jesus’ living, suffering, and death as an example and sacrament.
The eschatological break, or rather the reversal of direction occurred in the hiddenness of God in the crucified Christ. For, “crucified and hidden alone makes thoroughly clear that the hidden God cannot be a hypostasis in or behind God, but is the one living God who is manifest as he is concealed in the cross of Christ.” (Walther von Loewenich, “Martin Luther's Theology of the Cross,” 30.) At the Cross of Christ, God had once for all came to seek and save the lost. In contradistinction theologians of glory searched for God everywhere except the Cross of Christ.
One can follow the honing of the theology of the Cross following the Diet while Luther was masquerading as Knight George during his year-long exile at the Wartburg. While at the Wartburg Luther had ample opportunity to consider questions about true theology and true knowledge of God. During this time he was consistently drawn to the proclamation of Mary. He also continued to build on the foundation of the Psalms, Romans, and Hebrews lectures as well as the events at Heidelberg and Worms.
In his commentary on the Magnificat Luther elaborated on the reversal of direction in terms of the distinction between God hidden and God revealed: how experience becomes a means by which the Holy Spirit instructs us about who God is for us. As Luther wrote at the beginning of the commentary,
“In order properly to understand this sacred hymn of praise, we need to bear in mind that the Blessed Virgin Mary is speaking on the basis of her own experience, in which she was enlightened and instructed by the Holy Spirit. For no one can correctly understand God or His Word unless he has received such understanding immediately from the Holy Spirit. But no one can receive it from the Holy Spirit without experiencing, proving, and feeling it. In such experience the Holy Spirit instructs us as in His own school, outside of which nothing is learned but empty words and prattle.” (Martin Luther, LW 21, 299.)
Beginning in this manner, reversing the direction of experience and knowledge Luther collapsed the distance between God and man previously constructed by the scholastic theologians’ moral philosophy. God was no longer the terminus of the human ascent toward grace. Instead, everyone and everything was brought into immediate relation to God in a Subject-subject relationship so to speak; not in heaven but in the experience of conscience, in actual life. The distance collapsed and sinners were brought into immediate relationship with God when the crucified Christ himself came to Old Adam through the preaching of the Gospel. Moving in that way Luther appealed to experience, as he did at Worms, to name the reality of faith. He understood that correct knowledge of who God will be for us, "for you," is inseparable from the theology of the cross for they assert one and the same exclusive experience.