We skipped over a few chapters with some additional laws in them. Feel free to go back and read those if you would like. God now sends the people to attack Midian. He orders even the women to be killed, because it was the Midianite women who had enticed the men into the worship of another god.
God does not ask us to kill people like he did with Israel, but God does take turning people away from him very seriously. In Matthew 18:6, Jesus taught that if someone draws another person into sin, they would be better off committing suicide. We should be careful to always set a good example both in our beliefs and actions. We should also be careful to avoid those who want to turn us away from God’s truth.