According to the Preface to the Small Catechism, the teacher is to abide with rigid exactness by the text which he has once chosen and have the children learn it verbatim. "In the first place," says Luther, "let the preacher above all be careful to avoid many kinds of or various texts and forms of the Ten Commandments, the Lord's Prayer, the Creed, the Sacraments, etc., but choose one form to which he adheres, and which he inculcates all the time, year after year. For young and simple people must be taught by uniform, settled texts and forms, otherwise they easily become confused when the teacher to-day teaches them thus, and in a year some other way, as if he wished to make improvements, and thus all effort and labor will be lost. Also our blessed fathers understood this well; for they all used the same form of the Lord's Prayer, the Creed, and the Ten Commandments. Therefore we, too, should teach the young and simple people these parts in such a way as not to change a syllable, or set them forth and repeat them one year differently than in another. Hence, choose whatever form you please, and adhere to it forever. But when you preach in the presence of learned and intelligent men, you may exhibit your skill and may present these parts in as varied and intricate ways and give them as masterly turns as you are able. But with the young people stick to one fixed, permanent form and manner, and teach them, first of all, these parts, namely, the Ten Commandments, the Creed, the Lord's Prayer, etc., according to the text, word for word, so that they, too, can repeat it in the same manner after you and commit it to memory." (533, 7ff.) Thus Luther indeed placed a high value on exact memorizing of the Catechism. As to the quantity of memorizing, however, Luther did not demand more than even the least gifted were well able to render. He was satisfied if they knew, as a minimum, the text of the first three chief parts and the words of institution of Baptism and the Lord's Supper. (579, 22. 25.) That was certainly not overburdening even a weak memory. Luther was right when he declared in his _Short Form of the Ten Commandments,_ of 1520: In the three chief parts everything "is summed up with such brevity and simplicity that no one can complain or offer the excuse that it is too much or too hard for him to remember what he must know for his salvation." (W. 7, 204.)