"This religious solo motet was composed when Mozart was staying in Milan during the production of his opera Lucio Silla which was being performed there in the Teatro Regio Ducal. It was written for the castrato Venanzio Rauzzini, who had sung the part of the primo uomo Cecilio in Lucio Silla the previous year. While waiting for the end of the run (from 26 December 1772 to 25 January 1773), Mozart composed the motet for his singer, whose technical excellence he admired. Its first performance took place at the Theatine Church on 17 January 1773, while Rauzzini was still singing in Mozart's opera at night. In modern times, the motet is usually sung by a female soprano." One wonder's if Bartoli is a natural female soprano...
