A critical review of the editio princeps of the Liber Timothei episcopi de Pascha recently published by Pierre Chambert-Protat and Camille Gerzaguet in the coll. Sources chrétiennes. The article questions the editors’ thesis, at length developed in the Introduction, that the text is only the Latin translation, also known by Gregorius of Elvira and St. Augustine, of a Greek treatise apparently due to one Timothy, bishop of Cybistra in Cappadocia during the first half of the IVth century (the translation would be a little later: the original and the version as well ought to be situated around the time of Nicaea, which applied to fixing the Easter date). It tries to show that this thesis, although not implausible, is not however as strong as its promoters imagine, and that several of their arguments are to be rejected or at least to be qualified. This discussion, which forms the main part of the article, is supplemented by two lists of proposed corrections: the first deals with the Latin text and the second, in an appendix, with its French translation.