They were so used to the complicated structure of figured music, with its canons, fugal intricacies, imitations and inversions, that they could not even imagine a music that should be simple and straightforward, retaining the essential features of vocal harmony, and yet allowing the words on which it was composed to be distinctly heard.

The Cardinals rebutted these objections by pointing to the Te Deum of Costanzo Festa (a piece which has been always sung on the election of a new Pope from that day to our own times) and to the Improperia of Palestrina, which also holds its own in the service of the Sistine.

But the singers answered that these were exceptional pieces, which, though they might fulfill the requirements of the Congregation of Reform, could not be taken as the sole models for compositions involving such variety and length of execution as the Mass.
Their answer proved conclusively to what extent the contrapuntal style had dissociated itself from the right object of all vocal music, that of interpreting, enforcing, and transfiguring the words with which it deals, and how it had become a mere art for the scientific development of irrelevant and often impertinent melodic themes.
In order to avoid an absolute deadlock, which might have resulted in the sacrifice of ecclesiastical harmony, and have inflicted a death-blow on modern music, the committee agreed to refer their difficulties to Palestrina.

On the principle of _solvitur ambulando_, he was invited to study the problem, and to produce a trial piece which should satisfy the conditions exacted by the Congregation as well as the requirements of the artists.

Literally, he received commission to write a Mass in sober ecclesiastical style, free from all impure and light suggestions in the themes, the melodies and the rhythms, which should allow the sacred words in their full sense to be distinctly heard, without sacrificing vocal harmony and the customary interlacing of fugued passages.