It is an old and tired stereotype that Luther’s chief accomplishment was to chuck out everything in the Christian past and start fresh, the one exception being the Bible. Luther did insist that the written Scriptures were both the source of true knowledge about God and the final testing place for all Christian practices, but he would hardly have written volumes about the faith himself if there weren’t a place for explanation and interpretation in the life of the church!
And Luther was profoundly inspired by Christian writers and theologians of the past. There’s no Luther without the Creeds, no Luther without St. Augustine, no Luther without the Greek fathers, and—most surprising to those who equate Protestantism with rationalism—no Luther without the medieval Catholic mystics!
One of the most influential theologians for Luther was St. Bernard of Clairvaux, a Cistercian abbot of the 11th and 12th centuries. His most famous work is the treatise On Loving God, which Luther knew and loved. In places it describes the soul or the church as a bride and Christ as the bridegroom. For example, in Bk. IV he writes:
“But the believing soul longs and faints for God; she rests sweetly in the contemplation of Him. She glories in the reproach of the Cross, until the glory of His face shall be revealed. Like the Bride, the dove of Christ, that is covered with silver wings (Ps. 68.13), white with innocence and purity, she reposes in the thought of Thine abundant kindness, Lord Jesus… Rightly then may she exult, ‘His left hand is under my head and His right hand doth embrace me.’ The left hand signifies the memory of that matchless love, which moved Him to lay down His life for His friends; and the right hand is the Beatific Vision which He hath promised to His own, and the delight they have in His presence. The Psalmist sings rapturously, ‘At Thy right hand there is pleasure for evermore’ (Ps. 16.11): so we are warranted in explaining the right hand as that divine and deifying joy of His presence.”
This nuptial mysticism appears in one of Luther’s earliest and most important works, The Freedom of a Christian (sometimes also called Concerning Christian Liberty). The work is divided into two parts, the first explaining how “a Christian is a perfectly free lord of all, subject to none,” and the second describing how “a Christian is a perfectly dutiful servant of all, subject to all.” In the first half, Luther details the “incomparable benefits of faith” in Christ. One of things faith does is “unites the soul with Christ as a bride is united with her bridegroom” (LW 31:351). And this is the benefit:
“Christ is full of grace, life, and salvation. The soul is full of sins, death, and damnation. Now let faith come between them and sins, death, and damnation will be Christ’s, while grace, life, and salvation will be the soul’s; for if Christ is a bridegroom, he must take upon himself the things which are his bride’s and bestow upon her the things that are his. If he gives her his body and very self, how shall he not give her all that is his? And if he takes the body of the bride, how shall he not take all that is hers?” (LW 31:351)