A Treatise on the New Testament, That Is, the Holy Mass

In the summer of 1520, between The Treatise on Good Works and The Babylonian Captivity of the Church, Martin Luther published a short German pamphlet with the title Ein Sermon von dem neuen Testament, das ist von der heiligen Messe. It belongs to a sequence of writings on the Lord's Supper that began with his 1519 sermon on the sacrament of the body of Christ, and it was written for ordinary readers rather than for scholars. Luther had already attacked the trade in indulgences; here he turned to the practice that sat at the center of late medieval devotion and parish economy alike, the mass, and especially its multiplication in private, endowed, and votive celebrations offered for the living and the dead. He wrote in the vernacular because the people whose piety and money sustained that system needed to hear what the mass was for.

The argument hangs on a single word. At the Last Supper Christ called the cup the new testament in his blood, and Luther takes testament in its plain legal sense: a last will, made by one who is about to die, bequeathing something to named heirs. A testament requires a testator, an inheritance, heirs, a written promise, and a seal. Christ is the testator, the inheritance is the forgiveness of sins and eternal life, the heirs are those who believe, the promise is the words of institution, and the bread and wine are the seal that confirms the bequest. From this Luther draws the conclusion that governs the whole treatise. A testament is something received, not something offered. The mass therefore cannot be a sacrifice that the priest presents to God on behalf of others; it is a gift that God presents to the faithful, and the only fitting response is faith that takes the promise at its word. Because the promise is the heart of the sacrament, Luther insists that the words of institution should be spoken aloud and in German rather than murmured in Latin, so that the heirs can actually hear their inheritance read. He commends receiving both bread and cup while declining to make it a point of compulsion. What remains of sacrifice is real but relocated: the believer offers prayer, praise, thanksgiving, and the self, and offers them through Christ, which is a priesthood that belongs to every Christian and not to a clerical order. The masses said for money, the brotherhoods, and the anxious accumulation of merits are measured against this and found to have inverted the whole transaction.

The treatise matters because it supplies the positive teaching that The Babylonian Captivity would state polemically a few months later, and because its categories of promise, sign, and faith became the grammar of Protestant sacramental thought. It is also a clear instance of Luther's habit of resolving a vast institutional question by pressing on a single scriptural phrase.

Who should read this: readers who want Luther's eucharistic teaching in his own pastoral voice before the controversies hardened it, and anyone tracing how justification by faith reshaped worship. It is not for those seeking a balanced account of the medieval mass or a treatment of Luther's later disputes with Zwingli and Karlstadt, which lie outside its frame.