Do Not Be Afraid! When the people were to see their enemy, stronger and more numerous than themselves, God would be with them, and they should not fear.
Instructions from Officers were to be obeyed, and some of them were as such: if you have not dedicated your house, then dedicate it so it will be done in case you die in battle; if you have planted a vineyard, go home and eat of it; if you are engaged to a woman, go and marry her; if you are afraid, go home. After all of these instructions are obeyed, then the army can go to batle.
Offer of Peace to Far-away Cities – When approaching a city far from their land, they were to first to offer peace to the city. If they accept the offer of peace, then they should be placed under tribute to the conquering force. If not, they were to be conquered and plundered.
Utter Destruction of People in Cities of Inheritance – cities within the promised land were to be taken without prejudice. Every enemy was to be driven out and killed. No one was to be left alive, unless they were to teach the Israelites their fall religions.
Siege Materials – when Israel was besieging a city, they were not to cut down or destroy trees that produced fruit. Only trees that were not good for fruit were to be cut down and used for battle.
Unsolved Murders – When a dead body was found, the leaders of the nearest city were to break the neck of a heifer as an act of justice for the dead. Then, the guilt of the innocent blood would be put away from the city.
These instructions are so varied in their scope, it is difficult to pull them into a cohesive point, However, let it suffice to say that God was giving instructions to all the people of Israel to go just warfare, and not to kill indiscriminately.