Luther’s Writing Against Emerging Sabbatarianism
by Dr. Lowell H. Zuck
Retired as United Church Professor of Theology and History at Eden Theological Seminary, Dr. Zuck continues as research consultant in the Eden Archives. He edited vol. 4 of “Living Theological Heritage of the U.C.C.” (1999), and has worked for years with Robert Kolb through the Center for Reformation Research.
An earlier version of this short article was prepared for presentation to Heiko Oberman’s seminar at the Erfurt Luther Congress. The life and work of Heiko (d., 2001) is gratefully remembered, along with appreciation for a recent gift to the Eden Seminary Library from Reinhard Groscurth of a 1556 Wittenberg Luther publication including the 1538 letter about sabbatarians.
Luther’s open letter of 1538 condemning Sabbatarian tendencies among Christians in Silesia and Moravia after 1527 is a key work marking the transition toward the anti-Judaic attitudes of the late Luther. Marked by a new severity toward the Jews on Luther’s part, the letter had its origin in Luther’s response to a new Sabbatarianism arising among radical Protestants, which Luther saw as a victory for Jewish legalism over sound evangelical teachings. Before looking at the structure and argument of Luther’s letter, we shall look briefly at the minor involvement of Sabbatariansim, which evidently arose as a secondary issue among Luther’s sectarian, Anabaptist critics.
It is interesting that Andreas Karlstadt, one of Luther’s first theological opponents, already in 1524 published Von dem Sabbat un gebotten feyertagen at Jena, reflecting his pastoral concerns at Orlamuende, tr. E. J. Furcha, tr., The Essential Karlstadt, Scottdale PA, 1995, pp. 317-333. In section 9, pp. 333-4, Karlstadt says, “It is no secret that human beings instituted Sunday. As for Saturday, the matter is still being debated. But it is clear that you must celebrate on the seventh day and allow your servants to celebrate whenever they have worked six days.”
The first polemical appearance of Sabbatarianism in the Reformation coincides with Luther’s knowledge of it and his refutation of the Silesian movement in this work. Yet there were preliminary written refutations of the same Sabbatarians, including two by the Spiritualist-leaning Lutheran, Valentin Crautwald, around 1530, and major refutation by Crautwald’s Spiritualist master, the Silesian Kaspar Schwenkfeld, who had responded in 1532 to the request of the overburdened Wolfgang Capito inStrassburg for a refutation of a now lost Sabbatarian writing by the German Anabaptist leader, Oswald Glait (1490-1546). It is curious that Luther and Schwenckfeld, so often at odds with each other, both came to write polemical works against a common enemy, the Sabbatarian Anabaptist future martyr, Oswald Glait, with similar conclusions but done from the differing standpoints of the Evangelical and the Spiritualist reformations.
Little is known about Oswald Glait, a founder with Andreas Fischer, (1480-1546) of Sabbatarian Anabaptism, both of whom developed the seventh-day doctrine into a major part of their faith. Glait, born at Cham in the Upper Palatinate, later came to serve a Lutheran congregation at Nikolsburg, Moravia, after 1525 under the protection of Leonhard von Liechtenstein. At first helping unite the evangelical groups at a 1526 Austerlitz synod, Glait became an Anabaptist when Balthasar Huebmaier arrived at Nikolsburg the same year. The Liechtenstein Lord also approved of Anabaptism. When Glait sided with the radical Anabaptist Hans Hut against the use of the sword one year later, they were both exiled to Vienna. Moving on to Liegnitz, Silesia, where Schwwenckfeld and Crautwald were influential, Glait (aided by Andreas Fischer) appears to have become a Sabbatarian there, where he published a lost tract “Concerning the Keeping of the Sabbath,” c. 1530.
Glait taught that the seventh day Sabbath is binding on Christians just as it was on the Jews of old, because it is enjoined in the Decalogue. In his 24-verse hymn on the Ten Commandments, not yet literalistic on the seventh day Sabbath, verse 12 is as follows:
Mein Sabbath solt du halted
Im gaist, wie ichs begeer,
Dein hertz solt du nit spalten,
Solt fassen meine leer,
Im gaist, wie ichs begeer,
Dein Leyb un Seel halt wol in huet,
Das sie meinem willen volgen
Mit frieschan freiem muet.
The Sabbatarian issue involved a tendency toward literalism in interpreting both Old and New Testament, which was prominent among Anabaptists, while at the same time many of their leaders (like Schwenckfeld) were inclined toward spiritualizing types of Biblical exegesis, which were usually unacceptable to Luther. Glaits’ hymn on the Ten Commandments combined literal and spiritual exegesis in a way familiar to Anabaptists.
Crautwald and Schwenckfeld emphasized more than Luther a spiritualizing interpretation of the Sabbath in order to refute keeping the seventh-day, but the conclusions of all three are similar nevertheless. In rejecting Glait’s main argument, Schwenckfeld pointed out that following the Decalogue literally would mean reinstating the whole Judaic law, including circumcision. Schwenckfeld’s view on the other hand was that “the true observers of the Sabbath are those upon whose hearts the law of the Spirit has been written by the fingers of God.” Although Schwenckfeldian in language, this conclusion closely resembles Luther’s basic reference to the necessity for relying upon a new covenant (Jer. 31:31) in his work against Sabbatarians.
Evidence is scanty for the further development of Anabaptist or other kinds of Sabbatariansm. We have here observed its emergence with Glait and Fischer at Liegnitz, Silesia and with Fischer at Nikolsburg, Vienna and Liegnitz, the Sabbatariain Anabaptist Glait was also expelled from Prussia in 1532 by the order of Duke Albert. It is likely that he now traveled on to Falkenau in Bohemia, not far over the border from Silesia, where Count Wolfgang Schlick zu Falkenau reported about the same time to Luther that Jews were making inroads through the countryside. The alarmed Count Wolfgang wrote Luther that Jews had already induced some Christians to become circumcised, and were succeeding in spreading the false teaching that since the Messiah had not yet appeared the Jewish law must be adopted by all the Gentiles. The count’s further request for ways to refute Jewish teachings from Scripture provided the basis for Luther’s letter against the Sabbatarians to his friend in Bohemia. It is possible that when Pentecost 1528 passed without realizing Hut’s prediction for the apocalyptic end of history, his students, Glait and Fischer, especially the latter, were moved to bring order to infant sabbatarian communities by rejecting chiliastic speculation and past marital irregularity.
Luther assumed that Jewish agitation and efforts at proselyting lay at the roots of the Sabbatarian movement, and he wrote his treaties accordingly. Luther’s strong emphasis upon Christian freedom based upon a clear distinction between law and Gospel made him oppose Sabbatarianism. There is little direct evidence of Jewish influence upon Sabbatariansim this early. In a 1532 table reference Luther spoke generally of “the new error concerning the Sabbath.” In his 1535 “Lectures on Genesis,” Luther remarked more fully: “In our time there arose in Moravia a foolish kind of people, the Sabbatarians, who maintain that the Sabbath must be observed after the fashion of the Jews. Perhaps they will insist on circumcision also, for a like reason.” A few sentences later he referred to “the Jews and their apes, the Sabbatarians,” supporting the suspicion that the sabbatarian movement was probably Christian in origin.
By 1537, however, a new chill over Luther’s relations to the Jews entered his “Table Talk,” attributed to the notable Rabbi Josel of Rosheim’s efforts to secure safety and freedom for Jews in Saxony. We are told that “a letter was delivered to Dr. Martin from a certain Jew who requested and pleaded (as he had often written to the doctor before) that permission be obtained from the Elector to grant him safe entrance into and passage through the Elector’s principality. Dr. Martin responded, ‘Why should these rascals, who injure people in body and property and who withdraw many Christians to their superstitions, be given permission? In Moravia they have circumcised many Christians and call them by the new name of Sabbatarians…I’ll write this Jew not to return.”
Elector John Frederick of Saxony in 1536 had forbidden Jews to reside or travel through his territory. Luther’s reply to Rabbi Josel’s request for Luther to intercede with the authorities on behalf of the Jews was negative. It closed with a possible reference to Luther’s writing against the Sabbatarians:
My dear Josel: I would have gladly interceded for you, both orally and in writing, before my gracious lord (the elector), just as my writing have greatly served the whole of Jewry. But because your people so shamefully misuse this service of mine and undertake things that we Christians simply shall not bear from you, they themselves have robbed me of all the influence I might otherwise have been able to exercise before princes and lords on your behalf.
For my opinion was, and still is, that one should treat the Jews in a kindly manner, that God may perhaps look graciously upon them and bring them to their Messiah—but not so that through my good will and influence they might be strengthened in their error and become still more bothersome.
I propose to write a pamphlet about this if God gives me space and time, to see if I cannot win some from your venerable tribe of the patriarchs and prophets and bring them to your promised Messiah.
In 1538 the Saxon prohibition against Jews was removed, although Luther had no part in it. Evidently Jewish-Christian relations became less strained after that, prior to beginnings of another Sabbatarian movement associated with Francis David in Siebenbuergen (Transylvania) in 1558. A continuing Sabbatarian minority derived from the local Unitarian majority near Cluj in Romanian in 1588, under Szekler nobleman named Andreas Eossi, expelled by the Unitarians in 1623, actually became Jewish and survived until German persecution in 1941.
Luther’s three last writings against the Jews in 1543 (not discussed here) were such vulgar and harsh attacks that even some of his contemporaries were offended, according to Mark U. Edwards, Jr. They may or may not have had some connection with Luther’s 1538 letter, considered here. Explanations for the latter works are unclear. Clearly, Luther was greatly disappointed at the end of his life that the Jews were not being converted.
We turn now to the structure and argument of Luther’s letter against the Sabbatarians. Only a few months after Luther wrote to Rabbi Josel promising a missionary pamphlet directed toward the Jews, Luther’s “Letter to a Good Friend: Against the Sabbatarians” was published at Wittenberg (March 1538). The torie of Luther’s writings does not fit his promised apologetic purpose. He expresses much pessimism regarding prospects of converting Jews, and, he explains, is chiefly interested in strengthening Christians to resist the Jews and to refute their arguments. The writing nevertheless corresponds more closely than any other Luther work to the intention expressed in the letter Rabbi Josel. As the title indicates, Luther’s letter was addressed to “a good friend.” John Mathesius in 1566 identified the good friend as Count Wolfgang Schlick zu Falkenau, a prominent member of a Moravian family sympathetic to the Reformation. Informed by the count that Jews had been proselyting in Bohemia and Moravia and had convinced some Christians that they should be circumcised, that the Messiah had not yet come, that the Jewish law was eternally valid, and that it should be observed by Gentiles, Luther intended with this open letter to explain how these arguments of the Jews should be refuted with Scripture.
Luther’s serious theological argument answered three questions in two main parts. The questions were: what Jewish sin has brought them 1,500 years of suffering?; what does the promise of the new covenant (Jeremiah 31:31ff) mean for suffering people?; and, is the Mosaic law valid for all time? Underlying Luther’s understanding of the Jewish question were his basic assumptions, viz., the unity of all Scripture, Old and New Testament alike, and at the same time, the basic impact of the activity of the divine Trinity and of the incarnation of the Savior throughout the whole Bible. Luther was troubled above all by the unbelief of the Jews in the God and Savior he found to be revealed in the Bible.
Luther began with what he called the old argument Nicholas of Lyra used against the Jews (which Luther had previously outlined in his Genesis lecture), and which they have not been able to refute to the present, he claimed: “The Jews have been living away from Jerusalem, in exile for 1,500 years, without temple, divine service, priesthood, and kingdom…What is the sin which has caused God to punish them so cruelly, over so long a time?” It is not correct; Luther went on, to say like the Rabbis that the sin of the Jews was praying to the golden calf. That punishment was temporarily limited and God overcame it though leading his people into the Promised Land. Many other sins were committed under Moses. Many and graver sins were committed before the Babylonian captivity than before the Roman captivity. Yet the Babylonian captivity did not last more than seventy years, and the Jews were much comforted at that time with prophets, princes, and the promise. Here Luther brought in the promise of the new covenant in Jeremiah 31:31 in order to show that God desires to bring in a new covenant, eternally forgetting and forgiving pervious sins. In fact, it was precisely because they had not kept the old covenant that God wished to make a new covenant, eternally forgetting and forgiving previous sins. In fact, it was precisely because they had not kept the old covenant that God wished to make a new covenant which they could keep. This showed that the Jews were lying when they claimed that the advent of the Messiah was delayed by their sins. God’s promises were not contingent upon the Jew’s behavior. The conclusion seemed inescapable to Luther:
Since it is clear and obvious that the Jews are unable to name a sin because of which God should delay so long with his promise and thus be a liar in this matter, and that even if they could mention one or more, God’s word still stamps them as liars, since he assures them that he will never fail because of their sins in his promise to send the Messiah and to preserve the throne of David forever—it follows incontestably that one of the following two things must be true: either the Messiah must have come fifteen hundred years ago, or God must have lied (may God forgive me for speaking so irreverently!) and has not kept his promise.
Luther then indicates his belief that God has abandoned the Jews:
There is no prophet, and they have no word from Scripture telling them how long this exile will endure. They must be so pitifully afflicted for an indefinite time, wandering aimlessly about without prophets or God’s word. God never did this before, and he would not do it now if his Messiah had not come and his promise had not been fulfilled. For he promised that David’s throne would not fail or the priestly sacrifices be discontinues; and yet both David’s throne and Moses’ altar, together with Jerusalem itself, have been destroyed and have lain desolate for fifteen hundred years. Meanwhile God keeps silent, as he never did in Egypt or in the other exile.
The reference to the “silence of God” resembles laments of post-Holocaust Jewish scholars and others in the present-day world. In that context we might regard Luther’s view as over-confident in the face of recent world tragedies. On the other hand, what appears to be a restoration of Israel in the last century might convey today something resembling a salvation-history perspective, familiar to Luther, and especially held by his Reformed opponents, indicating that God has not abandoned the Jewish people or anyone else after all. By calling on evidence from history, as he did here, Luther adopted an interpretation holding to biblical respect for the reality of God’s action in history, which may or may not be of continuing relevance. More respect for the place of the Jews in history (as well as Muslims) would appear to be in order for us today, not to speak of the continuing validity of a positive Jewish history presented in Romans 9-11, which Luther apparently overlooked in this work.
The second question about Messianic salvation sharpened Luther’s accusation concerning the nature of Jewish sins. If the Messiah has not yet come, then the viewpoint of the Sabbatarians must prevail: Christians like Jews should all be circumcised and keep the Sabbath law along with all those who still await the Messiah. For Luther everything hinges around belief that the messianic promise has been fulfilled in Christ. From his evangelical perspective, the divine promise outweighs human sin, including the much talked-about sin of the Jews. “Why,” he says, “should God forget his promise so woefully in this exile or let it fail of fulfillment…since they have no sin which they can name, and yet this promise of the Messiah is the most glorious…upon which all other prophecy, promise and the entire law are built?” “The Jews may say what they want about the sins for which they are suffering (for they are lying). God did not promise an eternal throne to their sins or their righteousness, but to David… Since David’s throne which God declares is not to be destroyed or fall, has now been destroyed for 1,5000 years, it is incontrovertible that either the Messiah came 1,500 years ago and occupied the throne of his father, David, and forever occupies it, or God has become a liar.”
Again, the sin of the Jews for Luther is rejecting Christ. The Messiah has come with Christ and the new covenant repudiates the old law. Messianic salvation prevails over legalistic anxiousness. In the conclusion of part one, Luther affirms stoutly that he knows his argument to be true and “where they are still reasonable Jews, it must move them” and even upset the obdurate ones a little. With increasing hardness, Luther asserts that “we have nevertheless substantiated our own faith,” even if the argument does not convince many unbelieving Jews. Part two goes into considerable detail in countering the Jewish claim that the Mosaic Law is valid for all time. He here distinguished between a sense in which law is eternally valid, and a sense in which it is not. The Mosaic code Luther compares to the Sachsenspiegel, temporary social and economic laws prevailing in Luther’s own sixteenth century Saxony. On the other hand, the Ten Commandments are universally valid and indeed “prior to this had been implanted at creation in the hearts of all men.” But within the Ten Commandments themselves, Luther distinguishes between part which is temporary and part which is eternally valid. He believes, e.g., that the First Commandment is common to both Jews and Gentiles, but that the phrase “brought you out of the land of Egypt, out of the house of bondage” applies only to the Jews.
In a similar way, the Third Commandment concerning the Sabbath applies to the whole world. Yet Moses’ mention of the Seventh Day is a temporal adaptation for Jews only. “Nor was it to endure forever any more than was the whole law of Moses. But the sanctifying—that is, the teaching and preaching of God’s word, which is the true, genuine, and sole meaning of the commandment—has been from the beginning and pertains to all the world forever. Therefore, the Seventh Day doe not concern us Gentiles, nor did it concern the Jews beyond the advent of the Messiah.”
Here we come to the heart of Luther’s positive teaching about the Sabbath. As also in Luther’s Small and Large Catechism, he here insists that the importance of the Sabbath command is that we sanctify (heiligen) the day rather than merely celebrate it (feiern):
For God does not say: You shall celebrate the holy day or make it a Sabbath—that will take care of itself. No, you shall sanctify the holy day or the Sabbath. He is far more concerned about the sanctifying than about the celebrating of it. And where one or the other might be or must be neglected, it would be far better to neglect the celebrating than the sanctifying, since the commandment places the greater emphasis on the sanctifying and does not institute the Sabbath for its own sake, but for the sake of its being sanctified… Isaiah too declares in chapter 66:23 that the seventh day, or, as I call it, Moses’ adaptation of it, will cease at the time of the messiah when true sanctification and the word of God will appear richly. He says that there will be one Sabbath after another and one new moon after another, that is, that all will be sheer Sabbath, and there will no longer be any particular seventh day with six days in between. For the sanctifying or the word of God will enjoy full scope daily and abundantly, and every day will be a Sabbath.
Luther does not develop his understanding of Sabbath sanctification further in this work. But his view became the source of Protestant teaching regarding the Sabbath (cf. also a similar view in the Heidelberg Catechism, question 103, the Fourth Commandment), vis., that sanctifying the Sabbath is linked to friendly partaking in congregational divine worship. The Sabbath is understood as the Lord’s Day, on which the congregation assembles for divine worship, without compulsion. To the degree in which worship and the Lord’s Supper is a necessary source of Christian faith and life, the Sabbath takes on its original, indispensable meaning and renews it. The meaning is not that the Sabbath becomes only a “cultic day” over against a “profane” holiday. For Luther every day is sacred, and worship services may rightly be held on any day.
While Luther without doubt developed an over-drawn polemic against Jewish errors and god-forsakenness in this work, and unanswered questions remain for us today about the precise place of the Jews in the divine-human economy, Luther’s premature answers are not without a nourishing kernel of permanent truth about the rightful place of the Sabbath in human affairs, which is thoroughly Jewish. Reading the work carefully suggests that, much more than a bigot and long-term troublemaker in religious-racial tragedies, Luther in reality was a serious thinker about theological issues of great import and a person who above all sought to make his faith-commitments consistent, costly, and integral.
 Martin Luther, Against the Sabbatarians: Letter to a Good Friend, 1538, tr. In Luther’s Works (American Edition), St. Louis, 1971, Vol. 47, pp. 65-98; (Original in W. A. Weimar, 1883, ff., Vol. 50, pp. 312-337.
 See three short articles in the Oxford Encyclopedia of the Reformation, New York, 1996, by Daniel Liechty, Vol. 3, pp. 459-460 (“Sabbatarianism”); Vol. 2, pp. 176-177 (“Oswald Glait”), and Vol. 2 pp. 108-109 (“Andreas Fischer”). Also an article by Jeurgen Kaiser in Theologische Realenzyklopaedie, Berlin, 1988, Vol. 24, p. 530 (“Sabbat IV”).
 In E. J. Furcha, tr., The Essential Carlstadt (Scottdale, PA: Herald Press, 1995), 317-333, Section 9, p. 333-334.
 See and article by Douglas H. Shantz in Oxford Encyclopedia, Vol. 1, pp. 452-452 (“Valentin Crautwald”). Crautwald’s second writing, “Bericht un anzeig wie gar ohne Kunst und guten verstand Andreas Fischer vom Sabbath beschrieben,” is preserved in the Berlin Staatsarchiv in MS form. Fischer, and Anabaptist Sabbatarian friend of Glait, had replied to Crautwald’s refutation of Glait. Crautwald then wrote against Fischer. Crautwald, a former lector at the Liegnitz Dom, taught Greek to Schwenckfeld and was much influenced by him.
 Oxford Encyclopedia article, Vol. 4, pp. 21-24 by R. Emmet McLaughlin on “Kaspar Schwenckfeld.” The latter in 1532 refuted Glait’s lost book, “Concerning the Keeping of the Sabbath” (c. 1530) in his major tract, Vom Christlichen Sabbath und Unterschied des alten u neuen Testaments (1589), reprinted in Corpus Schwencfeldianorum, Leipzig, 1914, Vol. 4, pp. 4444-518. It was written as a letter to Leonhard von Liechtenstein of Nikolsburg, Moravia, who had sent Glait’s Sabbath-tract to Capito, asking for a refutation. Schwenckfeld agreed to answer Glait at Capito’s request.
 Oxford Encylopedia article, Vol. 1, pp. 259-260 by James Kittleson on “Wolfgang Captio,” who from 1526 to 1532 seemed to favor Anabaptists in Strassburg more than Bucer, but nevertheless withstood the Sabbatarian threat, himself writing a letter ot eh preachers supported by Leonhard von Liechtenstein in December 1531, found in Quellen zur Geschichte der Taeufer, ed. Krebs and Rott, Vol. 7, pp. 381-382. In 1539 Capito concluded his commentary on the creation story with a “Refutation of the Dreams of the Jews,” upon which he brought to bear his studies in the Talmud and in the Jewish commentaries. See James Kittleson, Capito, Leiden, 1975, p. 190.
 See Liechty article on Glait, (2) above, and R. F. Loserth in Mennonite Encyclopedia, Scottsdale, PA, 1955-59, Vol. 2, pp. 522-523. For more on Glait, see Liechty, Andreas Fischer and the Sabbatarian Anabaptist, Scottdale, PA, 1988, pp. 47-54. Also, Juergen Kaiser, “Ruhe der Seele und Siegel der Hoffnung: Die Deutung des Sabbats and den Reformation,” 1996, in Forschungen zur Kirchen- und Dogmengeschichte, Vol. 65.
 See Leichty article on Fishcer, (2) above and (6) above. See also George H. Williams, The Radical Reformation, Third Edition, Sixteenth Century Essays & Studies, Kirksville, MO 1992, pp. 624-625. Williams notes an entanglement of two possibly identical Fischers by Waclaw Urban, a Polish scholar, and Liechty, an American.
 Quoted in the Mennonite Encyclopedia, II, p. 523.
 The sixteen numbered sections in Crautwald’s work against Fischer resemble the eighteen numbered conclusions in Schwenckfeld’s work. #6 in Cruatwald, a reference to faith in Romans 3, for example, compares to #5 in Schwenckfeld, while Crautwald’s #8 referring to the implied necessity in James 2:10 for circumcision in addition to Sabbath-keeping, compares to #14 in Schwenkfeld’s conclusions.
 See Gerhard Hasel, “Capito, Schwenckfeld and Crautwald on Sabbatarian Anabaptist Theology,” Mennonite Quarterly Review Vol. 46, 1972, pp. 41-57, and R. Emmet McLaughlin, Caspar Schwenckfeld: Reluctant Radical, Yale, 1986.
 Luther’s Works, Vol. 54, pp. 51-52.
 Luther’s Works, Vol. 2 p. 361.
 Luther’s Works, Vol. 54, p. 239.
 W. A., Br 8, pp. 89 ff. In Luther’s Works, Vol. 47, p. 62.
 Mark U. Edwards, Jr., “Martin Luther,” in Reformation Europe: A Guide to Research, ed. Steven Ozment, St. Louis, MO, Center for Reformation Research, 1982, p. 70.
 Oxford Encyclopedia, article “Sabbatarainism,” Daniel Liechty, Vol. 3 p. 459.
 Ein Brieff D. Matt. Luther Wider die Sabbather An einen guten Fruend, W. A. 50, pp. 313-337. Luther’s Works, Vol. 47, pp. 65-98.
 Johannes Mathesius (1504-1565) was Luther’s first biographer and a reformer at Jachymov, in northern Bohemia. See article on him by Robert Rosin in Oxford Encyclopedia, Vol. 3, pp. 32-33.
 For an older commentrayr, see Reinhold Lewin,(died in a Nazi concentration camp), Luther’s Stellung zu den Juden, Berlin, 1911, pp. 66-77, or later, Heiko Oberman, The Roots of Anti-Semitism, Philadelphia: Fortress, 1984.
 Luther’s Works, Vol. 47, p. 66.
 Luther’s Works, Vol. 47, 73.
 Luther’s Works, Vol. 47, 75.
 Luther’s Works, Vol. 47, 77.
 Luther’s Works, Vol. 47, 78.
 Luther’s Works, Vol. 47, 90.
 Luther’s Works, Vol. 47, 92-93.
 Luther’s Works, vol. 47, 92-93.
 See article on “Sonn- und Feiertage” by Joachim Heubach in Evangelisches Staatslexikon, Stuttgart, 1975, pp. 55-66, and article, “Zacharias Ursinus” by Derk Visser in Oxford Encyclopedia, Vol. 4, pp. 202-203.