Lutheranism is a major branch of WesternChristianity that identifies with the teachings of the sixteenth-century German reformer Martin Luther. Luther's efforts to reestablish the theology and practice of the Roman Catholic Church and Carlstadt's Reform movement, launched the Protestant Reformation and, though it was not Luther's original intention, left Western Christianity divided. Augsburg Confession of 1530 established the Lutheran Church; while the 19th Ecumenical Council of Trent of 1543 officially chartered the Roman Catholic Church through the Roman Catholic Counter-Reformation. Prior to 1543, Catholics belonged to the old Western Catholic Church from which Martin Luther was an ordained Augustinian monk.
The split between Lutherans and Roman Catholics arose mainly over the doctrine of justification before God. Specifically, Lutheranism advocates a doctrine of justification "by grace alone through faith alone because of Christ alone," distinct from the Roman Catholic view of works in addition to faith. Lutheranism is also distinct from the Reformed Churches, another major church which arose during the Reformation. Unlike the Reformed Churches, Lutherans have retained many of the sacramental understandings and liturgical practices of the "Old Catholics". Lutheran theology differs considerably from Reformed theology in its understanding of divine grace, predestination, baptism, sacraments of the altar and to eternity after death.
Today, millions belong to Lutheran churches worldwide; furthermore, the world's 400 million Protestant Christians can trace their tradition, at least in part, back to Luther's reforming work.
The Book of Concord or Concordia (1580) is the historic doctrinal standard of the Lutheran Church, consisting of ten credal documents recognized as authoritative in Lutheranism since the 16th century. They are also known as the symbolical books of the Evangelical Lutheran Church. The Book of Concord has been categorized as a "body of doctrine" or corpus doctrinæ since it was intended to supplant the other German territorial copora doctrinæ like the Corpus doctrinæ Philippicum or Misnicum. It was compiled by Jakob Andreae and Martin Chemnitz at the behest of their rulers, who desired an end to the religious controversies in their territories that arose among Lutherans after the death of Martin Luther in 1546. The list of writings predating the Formula of Concord that would be included in the Book of Concord are listed and described in the "Rule and Norm" section of the Formula. The Book of Concord was published in German on June 25, 1580 in Dresden, the fiftieth anniversary of the presentation of the Augsburg Confession to Emperor Charles V at the Diet of Augsburg. The authoritative Latin edition was published in 1584 in Leipzig.