It is bible study right. Go biblical on her.
"If a thief be found breaking up, and be smitten that he die, there shall no blood be shed for him," Exodus 22:2
"They chose new gods; then was war in the gates: was there a shield or spear seen among forty thousand in Israel?" Judges 5:8
"Blessed be the LORD my strength which teacheth my hands to war, and my fingers to fight," Psalms 144:1.
"Then said he unto them, But now, he that hath a purse, let him take it, and likewise his scrip: and he that hath no sword, let him sell his garment, and buy one." Luke 22:36
"A righteous man who falters before the wicked is like a murky spring and a polluted well." Proverbs 25:26
"But if anyone does not provide for his own, and especially for those of his household, he has denied the faith and is worse than an unbeliever." For a man to provide shelter, food, clothing, money, and so forth is quite fine, but the man who refuses to defend his family and his community is a man in sin! 1 Timothy 5:8
"And for your lifeblood I will surely demand an accounting. I will demand an accounting from every animal. And from each man, too, I will demand an accounting for the life of his fellow man.
"Whoever sheds the blood of man, by man shall his blood be shed;for in the image of God has God made man". Gen 9:5-6