 However, the "Credo" had already been written and performed in 1878 and was initially conceived by Puccini as a self-contained work.Puccini never published the full manuscript of the "Messa", and although well received at the time, it was not performed again until 1952 (first in Chicago and then in Naples).However, he re-used some of its themes in other works, such as the Agnus Dei in his opera "Manon Lescaut" and the Kyrie in "Edgar".