Published at the end of 1537 or at the very beginning of 1538, the Cymbalum Mundi, a small French book containing “four poetic, very ancient, joyful and facetious dialogues”, was considered pernicious, godless and hateful by all contemporaries, Catholics as well as Protestants, and was soon suppressed by the authorities. This paper attempts to show that they were not mistaken : the author, Bonaventure Des Périers, thrusts his sword into the heart of Christian Revelation by mocking the Good News and the divine Word in particular. The Cymbalum thus represents an undeniably anti-Christian testimony, philosophically very mature, from the early 16th century and, as such, it certainly takes its place as a document of great importance for the religious history of Modern Europe.