The Church had to contend not only with persecution but also against error. In the centuries immediately after the time of the Apostles, Arius and other teachers contended that Jesus was not true God with the Father, but rather the first creature of God and like the Father. Christian bishops and their congregations rejected this false teaching and summed up the true faith in Scripture-based confessions. The Apostles', Nicene, and Athanasian Creeds, which we still confess today, come to us from this period of church history.
But gradually a number of false beliefs took root among Christians. A life without marriage or property, away from the world, came to be considered holier than a Christian life in the world. The bishop of Rome claimed to be "pope" (father), Christ's representative, the visible head of the church on earth. The Lord's Supper was changed into the mass, a daily unbloody repetition of Christ's sacrifice on the cross, celebrated by the priest for the benefit of the living and the dead. Christians were kept in uncertainty concerning their salvation and were directed not only to the merits of Christ but to their own works as a means to gain God's favor. The Savior was pictured as a stern Judge, who could best be approached through Mary and the other saints. Church teaching imposed punishments (penance) for sin; if the sinner did not bear his punishment during his lifetime, he was to suffer in purgatory after death. Indulgences were sold for the remission or reduction of such punishments. Baptism was still administered, the Lord's Supper was still celebrated (though only the bread was distributed to the people), and the Scriptures were still preserved and recopied; but the teachings of the Gospel were sadly obscured by false doctrines.
Luther hoped that the pope would hear the message of Scripture, so that the Church might be reformed. In Wittenberg, Germany, on October 31, 1517, he posted 95 Theses or sentences concerning indulgences. The Theses, together with Luther's other writings, were condemned by the Roman Church. Martin Luther himself was excommunicated for heresy, but continued to preach the Gospel in sermons, books, liturgies, and hymns. Contending for the truths of Scripture, the Reformer and his followers summed up their doctrine in Confession, which stated Biblical truths and rejected the contrary errors.
Besides the three ancient confessions of the Church, Lutherans adopted the Augsburg Confession, the Apology (Defense), the Smalcald Articles, the Large Catechism, the Small Catechism, and the Formula of Concord, all included in the Book of Concord of 1580. These Confessions distinguished the Lutherans not only from the Roman Catholic Church but also from the Reformed churches. The Reformed bodies broke away from the Roman Catholic Church, but rejected some Bible truths (for example, the real presence of Christ's body and blood in Holy Communion). Many of today's Protestant churches trace their history back to the Reformed churches of the Reformation and post-Reformation period.
Some of the Lutheran synods in the United States today are: the Evangelical Lutheran Church in America (ELCA); the Lutheran Church--Missouri Synod (LCMS); the Wisconsin Evangelical Lutheran Synod (WELS): the Evangelical Lutheran Synod (ELS); and the Church of the Lutheran Confession (CLC).