The word “apostasy” is a transliteration of the Greek apostasia, which originally denoted insurrection or secession. Its religious usage denotes the deliberate abandonment of one’s religion. Apostasy is closely related to heresy where the rejection of orthodox for heterodox beliefs and practices within a given religion is seen as a categorical denial of true religion. As such, apostasy must be understood as a public rather than a private occurrence. Apostasy is not a matter of private religious doubts or lapsed religious practices. Apostasy is a public renunciation and condemnation of one’s former religious beliefs and practices. The apostate often abandons one religion for another, but may renounce religion altogether.

III.I. Apostasy in Hellenistic Judaism

The Hebrew Bible strongly condemns the national apostasy of the ancient Israelites, who again and again reverted to the polytheistic religion and culture from which they emerged. But the first acts of individual apostasy occurred during the reign of Antiochus Epiphanes (c. 175–164 BCE), when many Jews were compelled by this pagan emperor to renounce their worship of God in favor of Greek gods. A passion for Hellenistic culture made serious inroads in Jewish religion and culture until the Maccabean Revolt, which succeeded in restoring Jewish Law and Jewish nationalism. Sporadic apostasy continued, but such abandonment of the Jewish Law was met with harshest condemnation within the Jewish community.

Under later Roman Rule, the Jews were allowed to practice their religion freely under the nominal political rule of a Jewish Tetrarchy. Sectarian movements flourished during this period, none more powerful than the Christian movement which in time separated itself from Judaism altogether. Sectarians and Christians were condemned as apostates. Moreover, such apostasy was condemned in political as well as religious terms because among the Jews, religion and citizenship were fused. Apostasy was seen as a crime against the state as well as a sin against God. The apostate was denied both salvation and citizenship.

III.II. Apostasy in Pagan Religions

In general, the idea of exclusivity was alien to Greek and Roman religions, given their polytheistic nature. The pagan cults did not expel members who adhered to rival religious traditions or philosophical circles. But often the gods of pagan religions were officially recognized by the civic authorities and identified with the well-being of the state. In such instances, the abandonment of politically sanctioned religions met with public criticism and even state-sponsored persecution. In the Greek East, Christians were accused of atheism because they rejected the gods of the people. In the Latin West, Christians were charged with abandoning the religion of their ancestors. On either charge, the early Christians who refused to pay respects to the civic gods were condemned and often persecuted for insurrection against the state. In short, apostasy only became a problem in pagan society when its ancestral customs or its civic gods were rejected.

III.III. Apostasy in the Christian Church

Many early Jewish and pagan converts to Christianity continued to observe Jewish ritual law or to participate in pagan religious festivals. In the beginning, the persistence of old religious customs was not regarded as apostasy. Apostasy only became a clear-cut issue when the Christian church had separated itself from Jewish and Gnostic forms of Christianity. Already in the New Testament, apostasy is associated with the false teachers and prophets whose appearance will signal the apocalyptic end of the age. In the early centuries, apostasy was largely an internal problem as orthodox Christianity separated itself from heretical and schismatic movements. But with the conversion of Constantine, apostasy became a civil offense punishable by law. Thus began more than a thousand years of mutual cooperation between Church and State. The State used the power of the sword to protect the Church against apostasy and the Church used the power of the scripture to protect the State against insurrection. Apostates were deprived of their civil as well as their religious rights.

The open abandonment of Christianity was rare where the bond between Church and State was firm, but even covert apostate movements were actively suppressed. Torture was freely employed to extract confessions and to encourage recantations. Apostates and schismatics were excommunicated from the Church and persecuted by the State.

Apostasy on a grand scale also occurred in Christian history. The so-called “Great Schism” between Eastern Orthodoxy and Western Catholicism in the 8th century marked the first great division within Christendom, resulting in mutual excommunication. The Protestant Reformation in the 16th century further divided Christian against Christian. Each sectarian group claimed to have recovered the authentic faith and practice of the New Testament Church, thereby relegating rival versions of Christianity to the status of apostasy.

Moreover, those Protestant churches which enjoyed territorial monopoly employed the weapons of religiously mandated excommunication and politically sponsored persecution against rival claimants to authentic Christianity. Only with the end of the religious wars and the enactment of edicts of toleration did such active political suppression of apostasy come to an end. Formal and informal religious sanctions were still imposed, ranging from excommunication and disinheritance to censure and shunning.

As this brief overview demonstrates, the condemnation of apostates has served as a “legitimation strategy” for all those religions in the past which made exclusivistic claims to be the only religion possessing the proper religious belief and practice. In national and territorial settings where political and religious loyalties were merged, legal as well as religious sanctions were imposed against apostasy. The apostate was deprived of citizenship as well as salvation. As such, the apostate was seen as a purveyor of falsehood and immorality that threatened the purity of the religious community and the stability of the political order.

Apostasy became less and less a problem in the modern world as religious traditions softened their dogmatic claims and as secular societies separated themselves from religious endorsement. The acceptance of religious pluralism and the privatization of religious faith in this century largely freed from the legal and religious odium of the apostate those individuals who changed their religion. To be sure, the Roman Catholic Church still retains the weapon of excommunication, Protestant Fundamentalists decry the dangers of heresy, and occasionally devout families may disown children who marry outside their faith or convert to another religion. But these sanctions do not carry the public or the private weight they once did. They are the ritual gestures of religious dogmatists who have lost their unquestioned authority in pluralistic and secularistic cultures.

IV. Apostasy in the Present