There are two categories of sin: sins against God and sins against man. By default, every sin is against God. Yet, not all sin is against man.
At times, God called people to enter into war with the goal of killing their enemies. The Bible clearly distinguishes between this type of killing and murder.
God places a high value on life. His desire was for man to be fruitful and multiply and bring forth abundantly in the earth (Genesis 9:7).
