During the xvith and xviith centuries, and in a context of religious struggles between Protestants and Catholics about the Eucharist, the Last Supper is more and more depicted in the Flemish painting. When the rite of the mass and the celebration of the Eucharist become the signs of preservation and triumph of the Catholic faith, painters give to the iconography of the Last Supper a ritual aspect and show the evangelical supper as the celebration of the first mass. Through the borrowing of some details to the liturgy of the mass, like Christ’s gesture or liturgical utensils, painters depict Christ as a priest. In this way, they create a visual continuity between Christ of the evangelical supper and the priest celebrating the contemporary mass. Faced with Protestant attacks, this process legitimates and justifies the rite of the mass of the Roman Church.