In 1773, M.P.G. de Chabanon provided the composer F.J. Gossec with the opportunity of writing his first « tragédie lyrique ». It was in the form of a libretto called Sabinus that had just been adapted from Chabanon’s 1762 tragedy, Eponine. The analysis of the opera shows how the two elements of an operatic work (text and music) adjust to the new aesthetic requirements of the 1770s. The bad reviews received by the work deserve to be examined closely, for they reveal that the fundamental function of music in an operatic work was still largely overlooked by most spectators.