Can you be a Christian and serve in the Military? Can you serve in a military service and not violate the will of God?
This is a question on which Christians are divided. The vast majority adhere to the belief that fighting in a war is entirely justifiable for a Christian. They draw on several biblical sources for this, including Paul's writings in Romans that the State is a legitimate authority charged with preserving order, that Christians should submit to; and also the fact that Jesus interacted with several soldiers and yet never commanded them to leave their profession. Most Christians would place limits on what kind of war is allowable, and what conduct is allowable within war, gathered together under the Just War theory.

A significant minority of Christians believe that fighting and killing are entirely incompatible with Christianity. Their basis is that commands such as "love your neighbour as yourself" and "turn the other cheek" cannot be compatible with attempting to kill your neighbour. While acknowleging that the State has the right and power to defend itself, they would say that Christians should play no part in such a war. Denominations that espouse this belief includes the Quakers and the Mennonites. Many of these have refused the draft and gone to jail for their beliefs; others have volunteered for non-combatant (but often still dangerous) war tasks such as stretcher bearers.