Ronald J. Sider
The Early Church on War and Killing
There are a substantial number of passages written over a period of many years that explicitly say that Christians must not and/or do not kill or join the military. Nine different Christian writers in 16 different treatises explicitly say that killing is wrong. Four writers in 5 treatises clearly argue that Christians do not and should not join the military. In addition, four writers in eight different works strongly imply that Christians should not join the military. At least eight times, five different authors apply the messianic prophecy about swords being beaten into ploughshares (Isa. 2:4) to Christ and his teaching. Ten different authors in at least 28 different places cite or allude to Jesus' teaching to love enemies, and, in at least nine of these places, they connect that teaching to some statement about Christians being peaceful, ignorant of war, opposed to attacking others, and so forth. All of this represents a considerable consensus.
Indeed, there is very little basis in the texts for describing the early Christian view as "divided and ambiguous." There are no authors who argue that killing or joining the military is permissible for Christians. On these questions, every writer who mentions the subject takes essentially the same position. Some pre-Constantinian Christian writers say more about these topics than others. Some do not discuss them at all. But to conclude from this relative silence or paucity of some surviving texts that other writers disagreed with the extant texts would be sheer speculation. The texts we have do not reflect any substantial disagreement. Every extant Christian statement on killing and war up until the time of Constantine says Christians must not kill, even in war.
That a growing number of Christians, especially in the late 3rd and early 4th centuries, acted contrary to that teaching is also clear. That in doing so they were following other Christian teachers and leaders who justified their conduct, we cannot deny with absolute certainty. But we have no evidence to support the suggestion that such teachers ever existed until the time of Constantine.
So why do scholars like Shean and Iosif argue that the teaching of the early church was divided and ambiguous? To answer that question, one must carefully examine their detailed arguments and interpretations of specific passages.
Shean argues that three of the most important Christian authors of the 3d century (St. Cyprian of Carthage, Clement of Alexandria, and Origen) were "ambivalent" and "did not explicitly object to military service for Christians." His only justification for such an argument in the case of Origen is that Origen prayed for the safety of the Roman Empire and those "fighting in a righteous cause." Origen argued that Christians, like pagan Roman priests, should be exempt from the Roman army since they also prayed for its success (Shean, 101; Contra Celsum, 8.73). But that statement comes in the middle of Origen's long, multi-book response to Celsus, a pagan Roman who had written about AD 180 that since Christians refuse to join the Roman army, the empire would collapse if everyone became a Christian. Repeatedly, in his long response, Origen says Christians love their enemies, do not take vengeance and do not go to war (e.g., Contra Celsum, 2.30; 3.8; 5.33; 7.26; 8.35; 8.73). Christ forbade the killing of anyone (3.7). War would end if all Romans became Christians (8.70). Christians, like the pagan priests who are exempt from military service, must keep their hands "unstained and free from human blood" (8.73). Text after text in Origen contradicts Shean's statement that Origen "did not explicitly object to military service."
No more convincing is Shean's statement that Cyprian and Clement were ambivalent because they used military metaphors. Both Shean and Iosif (as well as others) have argued that the frequent use of military metaphors for the Christian life suggests that the early Christians were not opposed to serving in the military. The problem with this argument is that even the most adamant Christian opponents of killing of any kind (e.g., Lactantius in his Divine Institutes) use military metaphors to describe the Christian's battle against sin and the devil. Cyprian used many military metaphors, but he said manslaughter is a mortal sin, insisted that Christians must not kill, and deplored killing of persons in both war and gladiatorial contests. Nowhere in any of the pre-Constantinian Christian authors have I found any evidence that the use of military metaphors suggested acceptance of Christians joining the army.