Unlike most religions in the Roman Empire, Christianity required its adherents to renounce all other gods, a practice adopted from Judaism. Christians' refusal to join pagan celebrations meant they were unable to participate in much of public life, which caused non-Christians–including government authorities–to fear that the Christians were angering the gods and thereby threatening the peace and prosperity of the Empire. In addition, the peculiar intimacy of Christian society and its secrecy about its religious practices spawned rumors that Christians were guilty of incest and cannibalism; the resulting persecutions, although usually local and sporadic, were a defining feature of Christian self-understanding until Christianity was legalized in the 4th century.[40][41] A series of more centrally organized persecutions of Christians emerged in the late 3rd century, when emperors decreed that the Empire's military, political, and economic crises were caused by angry gods.