Theists also, cannot kill people in the name of God. The moment the though enters into their mind, they become anti-theistic.
Numbers 31:
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And the Lord spoke to Moses, saying: "Take vengeance on the Midianites for the children of Israel. Afterward you shall be gathered to your people.” . . . And they warred against the Midianites, just as the Lord commanded Moses, and they killed all the males. They killed the kings of Midian with
the rest of those who were killed- Zur, Hur, and Reba, the five kings of Midian. Balaam the son of Beor they also killed with the sword.
And the children of Israel took the women of Midian captive, with their little ones, and took as spoil all their cattle, all their flocks, and all their goods. 10 They also burned with fire all the cities where they dwelt, and all their forts. they took all the spoil and all the booty—of man and beast.
Then they brought the captives, the booty, and the spoil to Moses, to Eleazar the priest, and to the congregation of the children of Israel, to the camp in the plains of Moab by the Jordan,
across from Jericho. And Moses, Eleazar the priest, and all the leaders of the congregation, went to meet them outside the camp. 1But Moses was angry with the officers of the army,
with the captains over thousands and captains over hundreds, who had come from the battle.
And Moses said to them: “Have you kept all the women alive? Look, these
women caused the children of Israel, through the counsel of Balaam, to trespass against the Lord in the incident of Peor, and there was a plague among the congregation of the Lord. Now therefore, kill every male among the little ones, and kill every woman who has known a man intimately. But keep alive for yourselves all the young girls who have not known a man intimately.
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So - these people were told by God to kill all the men, kill all the childen, and almost all the women. Except the virgins, rape them. As the Lord commanded.