The first of the two Cantatas written to Helbig’s words was designed for the Seventeenth Sunday after Trinity, which fell in 1720 on September 22.(400) Spitta conjectures(401) that Bach intended it for performance at Hamburg. In fact, his wife’s death postponed Bach’s visit to that town until November, by which date the Sunday appropriate to the Cantata had passed. Spitta holds that the Cantata may have been performed, after all, during the visit. Schweitzer is sceptical.(402) But Bach certainly expended great pains upon the score. The second Helbig Cantata(403) is for the Third Sunday in Advent, and the date of it would appear to have been 1721. It is one of the least agreeable of Bach’s works. Spitta (404) declares it a juvenile composition hastily adapted to a new libretto. Schweitzer(405) expresses the same opinion, and Sir Hubert Parry(406) finds the work “rather commonplace.” Its genuineness is discussed by Max Schreyer in the “Bach-Jahrbuch” for 1912, and more recently Rudolf Wustmann has insisted that it does not bear the stamp of Bach’s genius.(407) If it actually was composed in 1721, its production must have coincided with Bach’s second marriage on December 3 of that year.(408) In that case, his resort to old material is explicable. Only these two Cantatas were composed at Cöthen. But later, at Leipzig, two others were manufactured out of secular material written there.(409) It is unnecessary to refer to them, except to remark that in each case Bach appears to have been the author of the new libretto. In the first of them(410) it is clear that he was handicapped by the frankly secular metre of the original stanzas. The second of them,(411) originally a Birthday Ode to Prince Leopold of Anhalt-Cöthen, is a masterly conversion into a Whit-Monday text which, assuming that Bach wrote it, puts his literary facility beyond question. Bach made the last move in his professional career on May 31, 1723, when he was inducted Cantor of St. Thomas’ School at Leipzig, with particular charge of the Churches of St. Thomas and St. Nicolas. Here by far the greater number of his Cantatas appeared, and 172 of them survive. They are too numerous to be considered individually, and their classification is rendered difficult by the fact that the authorship of most of their libretti is conjectural and not ascertained. They fall, however, into two large categories, each of which exhibits characteristics of its own.