Lutheranism is a major branch of Protestantism that identifies primarily with the theology of Martin Luther, the 16th-century German monk and reformer whose efforts to reform the theology and practices of the Catholic Church launched the Reformation in 1517. Lutheranism subsequently became the state religion of many parts of Northern Europe.
In 1531, the split between Lutherans and the Roman Catholic Church was made public and clear with the Edict of Worms, in which the Diet condemned Luther and officially banned citizens of the Holy Roman Empire from defending or propagating Luther's ideas, subjecting advocates of Lutheranism to forfeiture of all property, with half forfeited to the imperial government and the remaining half forfeited to the accusing party.
The divide centered primarily on two points: the proper source of authority in the church, often called the formal principle of the Reformation, and the doctrine of justification, the material principle of Lutheran theology. Lutheranism advocates a doctrine of justification "by Grace alone through faith alone on the basis of Scripture alone", the doctrine that scripture is the final authority on all matters of faith. This contrasts with the belief of the Roman Catholic Church, defined at the Council of Trent, which contends that final authority comes from both Scripture and tradition.
Unlike Calvinism, Lutheranism retains many of the liturgical practices and sacramental teachings of the pre-Reformation Western Church, with a particular emphasis on the Eucharist, or Lord's Supper, although Eastern Lutheranism uses the Byzantine Rite. Lutheran theology differs from Reformed theology in Christology, divine grace, the purpose of God's Law, the concept of perseverance of the saints, and predestination, amongst other matters.