The Short Answer
Lactantius taught that a Christian cannot treat killing as an instrument of justice. In his reading of Jesus’ commands, the righteous person must not retaliate, must not take part in war, and must not bring an accusation that could lead to someone’s death. Justice, for Lactantius, is not passive weakness; it is active mercy, patient endurance, protection of the vulnerable, and reverence for human life as God’s creature.
Why This Question Matters
The hard part is not whether random violence is wrong. Nearly everyone agrees on that. The harder question is whether killing becomes righteous when it is public, legal, patriotic, or done in the name of order.
Lactantius pressed exactly there. He did not merely condemn private murder. He challenged the kinds of killing that society often calls lawful. His answer was stark: if God forbids killing, the follower of justice must not become a “companion and partner” in public killing.
That makes his teaching especially important for questions about war, capital punishment, revenge, prosecution, and whether Christians may defend good causes with deadly force.
What Scripture Says
Lactantius’s argument stands under Jesus’ teaching in the Sermon on the Mount. In Matthew 5:38-42, Jesus addresses retaliation and calls His disciples away from answering injury with injury. Lactantius connected this command with patience: the just person’s strength is revealed when he is wronged and refuses to strike back.
Jesus continues in Matthew 5:43-48, where He commands love for enemies. Lactantius’s reasoning follows that line closely. If all humans come from one Creator and share one life from God, then hatred—even hatred of the guilty—is a grave wickedness. Enmities are not to be started; they are to be removed.
That does not make justice indifferent to suffering. Jesus’ teaching about treasure in Matthew 6:19-21 fits Lactantius’s larger picture of righteousness: the just life is not built around earthly possession or self-protection, but around obedience to God and mercy toward those in need.
So the scriptural foundation is not simply “do not be violent.” It is deeper: do not retaliate, love enemies, treasure what God treasures, and practice a righteousness that entrusts judgment to God rather than seizing death as a tool.
How the Earliest Christians Understood This
Lactantius gives one of the clearest early Christian statements on killing and justice. In a discussion tied to Jesus’ words on nonresistance, he says that those who seek the path of justice must not participate in “public killing.” He explains that when God forbids killing, He is not only forbidding open violence already condemned by civil law; He is also warning against acts that society may approve as lawful. Therefore, he says, “it will not be lawful for a just man to take part in war because his warfare is justice itself.” See Lactantius in Nonresistance, Matthew 5:38-42.
He goes further. The just person must not accuse someone of a capital crime, because “it makes no difference whether you put a man to death by words or by the sword.” For Lactantius, the forbidden thing is not merely personal bloodlust. The forbidden thing is putting a human being to death. His conclusion is absolute: “there should be no exception at all,” because God willed man to be a sacred creature.
This explains why Lactantius could also say that religion must be defended “not by killing, but by dying,” and “not by cruelty, but by patient endurance.” Faith defended by bloodshed becomes polluted rather than protected. His words in Religion should be defended not by killing show that he did not think a holy cause made violence holy.
Yet Lactantius did not define justice as doing nothing. In his teaching connected with treasure in heaven and mercy, he calls the rescuing of captives an honorable exercise of justice. He says widows and orphans must be protected and assisted. Justice preserves life; it does not destroy it.
His teaching on enemy love also makes this personal. In Love Your Enemies, Matthew 5:43-48, Lactantius argues that because all people share one Father, those who plunder, torture, kill, and banish act against the law and right of human nature. In a nearby passage, he says the just person must not return insults, must avoid making enemies through his own fault, must endure harm calmly, and must leave vengeance to God: Lactantius on mercy and refusing revenge.
This was not an isolated concern among early Christian writers. Tertullian also spoke of murder as forbidden “once for all,” and Origen described Christians helping rulers by prayer rather than by taking up arms. Those witnesses do not carry the authority of Scripture, but they show that Lactantius stood within a recognizable early Christian pattern of reading Jesus’ commands seriously.
Common Misunderstandings
One misunderstanding is that Lactantius rejected justice. He did not. He rejected killing as a means of justice. He wanted captives rescued, widows and orphans protected, the poor treated with mercy, and enemies answered without hatred.
Another misunderstanding is that he only condemned private revenge. His words are broader. He specifically names war and capital accusation. For him, a killing does not become righteous simply because it is legal or public.
A third misunderstanding is that patience means cowardice. Lactantius saw patience as moral strength. The person who refuses retaliation under provocation is not defeated; the person who answers injury with violence is the one overcome.
What This Means for Christians Today
Lactantius forces Christians to ask whether “justice” has been defined by Jesus or by fear, anger, and public approval. If justice is shaped by Christ, then it cannot be separated from enemy love, mercy, and reverence for life.
That does not mean Christians ignore evil. Lactantius’s justice acts: it rescues, protects, gives, blesses, and endures. But it refuses to make death its servant. The Christian battle, as he put it, is justice itself—not the shedding of blood in the name of justice.
For believers wrestling with war, execution, revenge, or lethal defense of religion, Lactantius gives a searching answer: the way of Christ is not to defend righteousness by killing, but to bear witness through faithfulness, mercy, and patient endurance, leaving final judgment to God.
Keep Studying
- Jesus’ teaching on nonretaliation in Matthew 5:38-42
- Jesus’ command to love enemies in Matthew 5:43-48
- Lactantius on war, capital accusation, and public killing in Nonresistance, Matthew 5:38-42
- Lactantius on defending religion by patient endurance in Nonresistance, Matthew 5:38-42
- Lactantius on mercy toward enemies in Love Your Enemies, Matthew 5:43-48
- Lactantius on rescuing captives and helping widows and orphans in Treasure in Heaven, Matthew 6:19-21
- A later historical case study in The Christians During the Revolutionary War
