Decet Romanum Pontificem

(from Latin: "It Befits the Roman Pontiff"; 1521) is the papal bull that excommunicated the German theologian Martin Luther; its title comes from the first three Latin words of its text. It was issued on 3 January 1521 by Pope Leo X to effect the excommunication threatened in his earlier papal bull, (1520), for Luther had failed to recant. Luther had burned his copy of on 10 December 1520, at the Elster Gate in Wittenberg, to indicate his response.