Thus Luther extols it as the great achievement of his day that now every one knew the Catechism, whereas formerly Christian doctrine was unknown or at least not understood aright. And this achievement is preeminently a service which Luther rendered. He revived once more the ancient catechetical parts of doctrine, placed them in the proper Biblical light, permeated them with the Evangelical spirit, and explained them in conformity with the understanding of the Gospel which he had gained anew, stressing especially the _finis historiae_ (the divine purpose of the historical facts of Christianity, as recorded in the Second Article), the forgiveness of sins not by works of our own, but by grace, for Christ's sake. 86. Catechetical Instruction before Luther. In the Middle Ages the Lord's Prayer and the Creed were called the chief parts for sponsors (_Patenhauptstuecke_), since the canons required sponsors to know them, and at Baptism they were obligated to teach these parts to their godchildren. The children, then, were to learn the Creed and the Lord's Prayer from their parents and sponsors. Since the Carolingian Epoch these regulations of the Church were often repeated, as, for example, in the _Exhortation to the Christian Laity_ of the ninth century. From the same century dates the regulation that an explanation of the Creed and the Lord's Prayer should be found in every parish, self-evidently to facilitate preaching and the examination in confession. In confession, which, according to the Lateran Council, 1215, everybody was required to make at least once a year, the priests were to inquire also regarding this instruction and have the chief parts recited. Since the middle of the thirteenth century the Creed, the Lord's Prayer, together with the Benedicite, Gratias, Ave Maria, Psalms, and other matter, were taught also in the Latin schools, where probably Luther, too, learned them. In the _Instruction for Visitors,_ Melanchthon still mentions "der Kinder Handbuechlein, darin das Alphabet, Vaterunser, Glaub' und andere Gebet' innen stehen--Manual for Children, containing the alphabet, the Lord's Prayer, the Creed, and other prayers," as the first schoolbook. (W. 26, 237.) After the invention of printing, chart-impressions with pictures illustrating the Creed, the Lord's Prayer, and the Ten Commandments came into the possession also of some laymen. The poorer classes, however, had to content themselves with the charts in the churches, which especially Nicolaus of Cusa endeavored to introduce everywhere. (Herzog's _Realenzyklopaedie_ 10, 138.) They were followed by confessional booklets, prayer-booklets, and also by voluminous books of devotion. Apart from other trash, these contained confessional and communion prayers instructions on Repentance, Confession, and the Sacrament of the Altar; above all, however, a mirror of sins, intended as a guide for self-examination, on the basis of various lists of sins and catalogs of