“Mozart’s motet, Ave Verum Corpus, was composed in June of 1791, for his friend, Anton Stoll, a school teacher and choirmaster of the small parish church of St. Stephan in Baden, a spa-town located near Vienna which was famous for its hot thermal mineral springs. Mozart’s wife, Costanze, was pregnant with their sixth child and was ill, and so she was staying at the Baden spa for treatment (“taking the waters”).
The work was written almost as a payment to Stoll, who had often helped Mozart by making travel arrangements to and from Baden for Constanze. Writing very simply, Mozart was perhaps conscious of the limitations of a small-town choir, the manuscript for this work is dated June 17, 1791, and was presumably intended for the feast of Corpus Christi, which fell that year on June 23.”