This question was asked during a Bible study on Romans 13:8-10, which says,

Romans 13:8-10 (ESV) 8 Owe no one anything, except to love each other, for the one who loves another has fulfilled the law. 9 For the commandments, “You shall not commit adultery, You shall not murder, You shall not steal, You shall not covet,” and any other commandment, are summed up in this word: “You shall love your neighbor as yourself.” 10 Love does no wrong to a neighbor; therefore love is the fulfilling of the law.

The whole law of God can be summed up into two great commandments: Love God and love your neighbor as yourself. If you can do these things, you are fulfilling the law.

Now leave aside for the moment that even as redeemed sinners we are incapable of doing this perfectly. The point is that as we progress in our sanctification by the power and grace of the Holy Spirit, we should also be growing in our capacity to love our neighbor as ourself.

How do we understand this commandment to love as it pertains to our relationships whether that’s in our family toward our parents, toward our children, toward our spouses, or within the larger sphere of our community, or even the stranger in the next state, etc.? I think it is clear that the commandment to love “our neighbor as ourself” is not a command to love everyone equally in the same manner. My love toward my spouse will be different than my love toward my children, and both of those types of love will be different than my love for neighbors and friends, and that will be different than my love for a stranger whom I do not know.

How do I know this? Well, let’s consider the specific commands in the Bible as it deals with this various relationships. First, consider the 5th commandment: “Honor your father and your mother, that your days may be long in the land that the LORD your God is giving you” (Exodus 20:12). Children are to honor their parents. Not somebody else’s parents, not the stranger down the street, their own parents. This “honoring” of parents takes the form of obedience as we see in Ephesians 6:1. That’s how children show love toward their parents — obedience and honoring.

Next let us look at husband and wife. The institution of marriage was established at the beginning of creation in Genesis 2:24, “Therefore a man shall leave his father and his mother and hold fast to his wife, and they shall become one flesh.” Again note, a man shall leave his father and mother and cling to his wife and they shall become one flesh. A man does not enter into a “one flesh” union with everyone, only his wife. This command is supplemented in Ephesians 5:22-33 in which the wife is commanded to submit to her husband and the husband is commanded to love his wife. This is how love is expressed in the marriage relationship. In fact, if a man showed this kind of love to another woman other than his wife, then he has broken the 7th commandment to not commit adultery.

We could go on, but I believe the point is clear — the command to love your neighbor as yourself doesn’t mean you love the stranger in the same way or manner you love your children or your spouse. Each of these relationships have a context in which there is an appropriate way to express love. Furthermore, as it pertains to the neighbor, remember when Jesus was confronted by Jewish expert in the law, He was asked “who is my neighbor?” Jesus replied by telling the parable of the Good Samaritan. The lesson there is clear, your neighbor is anyone who crosses your path who is in need. The love we’re talking about is agape love, or the love of self-sacrifice. We’ve defined it as “love gives of itself to meet the needs of another.”

How does this apply to soldiers in war? Are they violating the commandment to love your neighbor as yourself? Are they violating the 6th commandment “you shall not kill?” A few things can be said on this point. First, war is a consequence of the fall of man. Because there is sin in the world and all men are sinners, there will be conflict. When you expand that conflict beyond the individual into the arena community or the nation as a whole, then you have war. War is inevitable in a sin-cursed world.

Second, theologians throughout the history of the church have argued for the concept of just war. In other words, there are circumstances in which not only is war inevitable, but also the moral thing to do. I don’t have space to expand on this properly, but consider WWII. Most people would agree that defeating Nazi Germany was the morally right thing to do.

Third, we do have Biblical examples in which God commands His very own people to engage in war. Consider the war of the conquest of the Promised Land. This was commanded and ordained of God. The Israelites were commanded to kill everyone and leave no one alive. Clearly God would not command His people to do something that was sinful; therefore, this particular incident could not be a violation of the 6th commandment. This same reasoning can be more broadly applied to the concept of just war. That is, it is not a violation of the 6th commandment to kill in war if the war is a just war.

As with all things in Scripture, context helps us to properly interpret and apply the truths we see revealed in the Bible.