“Truly this man was the Son of God!” (Mark 15:39).

These were the words of the centurion who was posted to watch over the crucifixion of Jesus Christ. This very same soldier was quite possibly the one who would later pierce the side of Jesus with his spear. He would spill the blood of atonement onto the place of the skull just as the waters of redemption splattered the golden limestone at his feet.

Soldiers and centurions play a huge role at every turn in the life of Jesus Christ. They are in Bethlehem on the heels of the wisemen, chasing the Son of Man to the banks of the Nile. John the Baptist washes them in the waters of the Jordan when the Spirit chases Jesus into the Negev to be tempted by Satan. They show greater faith than is found in all of Israel when, in Capernaum, one of them asks Jesus to just “say the word” that his boy may be healed. Soldiers arrest him in the Garden of Gethsemane when Jesus is betrayed with a kiss and his disciples disperse into the night. They receive him with blows when he is sentenced to death. They accompany him to the cross and reveal his identity as the Son of God at his death. Finally, they stand guard at the grave and witness his resurrection.

Some of these men do evil to Jesus, some do good. Obedience to their orders engages them in a brutal business.

Military life is not for the faint of heart. Even today, when it is possible to spend an entire enlistment at war and never see actual combat, the machinations of military life can be insidious to the soul. Modern propaganda bills military life as a right to be enjoyed and afforded to the underprivileged or marginalized demographic. I think the video games get it better when they name it a “Call of Duty.” As I learned in boot camp, “the military exists to kill people and destroy things.”

From time to time, the military may engage in goodwill, humanitarian gestures. They may perform rescue or salvage operations. But the military is not the Peace Corps. The MOOTW (military operations other than war) have a habit of becoming war as quickly as a Black Hawk falls out of the sky.

A Christian can never regard killing people and destroying things to be a right. That can only be a gross and heinous sin. Or it can be a duty done both out of an obligation to those God has put in authority over you and out of love for the community he has entrusted to your care. Yet this duty is still a brutal business that looks like a gross and heinous sin and often leads to despair.

The soldiers who came out to John at the Jordan asked him, “What shall we do [to bear fruit in keeping with repentance]?” (Luke 3: 8, 14). Martin Luther treats this passage in his treatise “On Whether Soldiers, Too, Can Be Saved.”

This work of Luther is not typically considered a “Letter of Spiritual Comfort” or “Trostbriefe.” Bear in mind, however, that he wrote it on behalf of Assa von Kram (sometimes spelled, Asche von Cramm) to give spiritual guidance to him and his military colleagues, and to comfort them because so many “soldiers are offended by their occupation itself,” (AE, 46:93) Luther goes on to detail how many soldiers give up all thought of God. They throw both their souls and consciences to the winds. In other words, then as now, soldiers had trouble reconciling their Christian faith with the horrors of war. They struggled to believe they could continue their occupation and remain in a state of grace.

Luther notes that John the Baptist did not ask the soldiers to quit their occupation. Instead, he tells them, “Rob no one by violence or by false accusation, and be content with your wages.” In this way “[John] praised the military profession” and “forbade its abuse” (p. 97). Keep in mind that these men were part of the Roman military. They were serving a pagan emperor in what many today would consider an unjust occupation of a foreign land. Yet, John the Baptist praises their service. They are serving the governing authorities who do not bear the sword in vain, but do so to punish evildoers and reward the good (Romans 13:1-4).

Luther will spend a good amount of time in the essay applying just war theory to a number of different conflicts. In doing so, he focuses mainly on the conflicts in Scandinavia and among the Hanseatic League. These form the backdrop for Bo Giertz’s treatment of these issues in his novel Faith Alone (forthcoming from 1517 Publications).

Luther highlights just how complicated it can be to discern the justness of a cause. Therefore, the heart of his advice to soldiers is never to trust in the justness of their cause any more than they should trust in the princes that order them to battle (Psalm 118:9; 146:3). Rather, when it comes to their salvation, they should trust in Jesus Christ alone. Only faith in Jesus Christ can make us righteous and “good in the sight of God” (p. 95) This Christian faith, however, is not incompatible with external righteousness that requires us to go to war in order to keep the peace when others would “rob, steal, kill, outrage women and children and take away property and honor” (p. 96).

War is a plague, but sometimes it needs to be fought to protect from greater plagues.

The advice of Luther not to put trust in the justness of one’s cause goes against the grain for many today. Certainly, he would not counsel people in a democracy to make war with no thought concerning the justness or rightness of their position. War is ugly. It should not be waged on a whim or for purely selfish reasons. Still, Luther understood that good soldiers and Christians may find themselves, for whatever reason, on the wrong side of a war. Even then, they can carry out their God-given vocation with honor. They can remember the centurion, occupying a foreign land, putting an innocent man to death, who would then declare, “Truly this man was the Son of God.”

The blood shed that day with a Roman spear was the blood that atoned for all sins, and the water that spattered the ground justified before God, even when just causes fail.