 Through the winter of 1858 – 59 Bizet worked on his first envoi , an opera buffa setting of Carlo Cambiaggio 's libretto Don Procopio . Under the terms of his prize , Bizet 's first envoi was supposed to be a mass , but after his Te Deum experience , he was averse to writing religious music . He was apprehensive about how this breach of the rules would be received at the Académie , but their response to Don Procopio was initially positive , with praise for the composer 's " easy and brilliant touch " and " youthful and bold style " . 
