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Book Summary – The Early Church on Killing: What Did the Early Church Teach about War and Killing?

This is part 1 of a 2 part series about the early church, killing and violence. Read part 2 here.

I recently finished Ronald J. Sider’s book “The Early Church on Killing.” He gathered all of the 2000 year old early church source data for Christians today to summarise the early church teachings on capital punishment, all forms of killing and participation in war.

His research question was, ” What did the early church think about war, abortion, and capital punishment? Then he compiled all early church teaching on the subject and presented it in this fantastic book. Early church writings are always interesting and Sider claims he made sure his research was comprehensive. So what did he find?

Top 7 Points from Early Church Documents

1. There are no church documents saying that Christians can kill or join the military before 313.

This is important because 313 AD was the year when the church transitioned from a serving fringe community to a ruling political organization. This change has damaged the church for the last 1500+ years and we look less like Jesus today because of this change.

2. We have 28 pre-constantinian church teachers in 57 documents that say Christians “must not kill” “do not kill” or “won’t join the military.”Chart = the early church on killing

3. Every type of killing is rejected in these church documents

Origin rejected “killing of every individual whatever” in his teaching. Tertullian taught the rejection of “every sort of man-killing” and Lactanius taught: “It is not permitted to commit homicide in any way.”

Sider concluded that the church rejected every type of killing saying, “The comprehensive rejection of killing includes abortion, capital punishment, gladiator contests, (even watching them), infanticide, and warfare.”

4. The primary reason for the early churches rejection of military service was not idolatry.

This argument is often used to justify military service and de-emphasize the New Testaments enemy love passages teaching. Jesus, the New Testament authors and early church leaders all believed enemy love was the only Christian ethic for disciples.

Regarding idolatry:

Tertullian wrote about idolatry often. He also gave other reasons than idolatry to reject military service. For example, he wrote that Christ “unbelted every soldier.” Most interpreters believe that Tertullian meant that Christ disarmed every violent person of his fighting equipment. Literally Jesus removed the weapons belt of every soldier.

Origin taught that all Christians need to reject military service for 3 main reasons:

  1. Disciples must love their enemies
  2. Disciples must reject any form of vengeance
  3. Christians do not shed human blood.

Christians in the first century rejected military service. The did it because Jesus’ rejected killing all human beings. Idolatry was not the primary reason that Christians chose to reject military service.

Jesus Christ standing and soldiers bowing down to him

5. The early church was united and firm on the issue of killing and military service.

There is little evidence for the popular argument that the church was divided and ambiguous regarding military service in all the pre-313 AD church documents.

Sider wrote, “No [early church] authors argue that killing or joining the military is permissible for Christians. On these questions, every writer who mentions the subjects takes essentially the same position.”

6. Augustine’s “Just War” theory did not come from pre-Constantinian church leaders.

Many early church theologians write their appreciation of the peace of Roman rule. But, “Origin is very clear that the new law taught by Christ explicitly forbids killing and warfare for Christians.”

7. During the late second century there are a few Christian soldiers.

In the mid-third century Origin “mocks and condemns” Christian soldiers. He points to the way they justify their military service and their worship of military idols. Then, by the early fourth century the numbers of Christian soldiers are large.

The early Christian writers united against military service. They argue against the justification’s for baptized members joining the military.

The primary documents do clearly show Christians starting to enter the military in the second century and the numbers going up over time. That is the reality we must face. (Comment below if you want me to go into the reasons for this growth at the time.)


Sider concluded his research with this:

What we can say with confidence is that every extant [existing early church] Christian statement on killing and war up until the time of Constantine says that Christians must not kill, even in war. That a growing number of Christians, especially in the late third and early fourth centuries, acted contrary to that teaching is also clear….But we have absolutely no evidence to support the suggestion that [teachers who supported just war] ever existed until the time of Constantine. Any claim that they did is sheer speculation.

The evangelical church of the Philippines is largely forgetting, missing or ignoring the peace and reconciliation teachings of scripture. And the peacebuilding and nonviolent model of Jesus. Most leaders and church members don’t see scripture’s ethics & peace teachings. They don’t know how to see these teachings because few teachers have highlighted them with the clarity and intentionality of Sider.

My dream is that the church centres herself on Jesus’ example and teaching once again as the soul of our faith.

What do Siders finding make you think about the church today?

This is part 1 of a 2 part series on the early church and violence. Read part 2 “How did the church get so violent?” here.

If you’re interested in the book you should buy a copy here on amazon. It’s an essential read if your interested in discussions about terrorism and church & state violence. This book is going to grow in importance as time marches on.

  • Nelson

    Please, elaborate on the reasons why Christians started entering the military in the second century. Also, if there are arguments against military service in the second century and evidence of Christians entering the military, then one can reasonably assume that there must’ve been Christian teachers arguing in favor of military service, too.

  • I’d be very interested to hear how it compares to Jean-Michel Hornus’s “It’s Not Lawful for Me to Fight”.