Among the clergy of St. Thomas’ during Bach’s Cantorate were two men, father and son, each of whom bore the name Christian Weiss. The elder was Pastor of the Church from 1714 till his death in 1737. He was a cultured man, in touch with the University, and possibly formed a link between it and Bach, to whom he showed greater cordiality than the Cantor received from other clerical colleagues. In 1732 his daughter, Dorothea Sophia stood godmother to Bach’s son, Johann Christoph Friedrich, afterwards famous as the “Bückeburg Bach.”(420) In 1737 his son stood sponsor to Bach’s daughter, Johanna Caroline.(421) Nor can it be altogether without significance that the names Dorothea, Sophia, Christian, are borne by others of Bach’s children by his second marriage. There is sufficient evidence, therefore, that Bach’s relations with the elder Weiss were intimate enough to support a literary partnership. Moreover, circumstances lend weight to the inference. For some years before Bach’s arrival in Leipzig, Weiss suffered from an affection of the throat which kept him from the pulpit. But, during the first year of Bach’s Cantorate, he was able to resume his preaching. If he was, in fact, the author of the libretti, we can have little difficulty in concluding that they and his sermons were built on the same text.
So far as they can be identified—the attempt is somewhat speculative—Weiss provided Bach with at least thirty-three libretti. He set five of them in 1723, three in 1724, nine in or about 1725, one in 1727, two in 1730, six in 1731, three in 1732, and four in the later Leipzig period.(422) Fourteen others bear a constructional resemblance to Weiss’s texts,(423) but their character refers them rather to Bach or Picander. Even so, if we do not exaggerate his activity, Weiss seems to have written at least one-sixth of the Leipzig libretti and more than a quarter of those of the earlier period. Without a doubt he eased a difficult situation in Bach’s experience before his regular association with Picander began.
Apart from their revelation of Christian Weiss, the libretti of Bach’s first year at Leipzig do not call for comment. Franck and Neumeister appear among them, and we trace Bach’s hand in nine.(424) But at Easter, 1724, he broke new ground with a libretto whence developed the Cantata form of his latest period.