And if a man lie not in wait, but God delivers him into his hand; then I will appoint you a place where he shall flee.
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Ambrose of Milan
AD 397
Even the person who unwittingly committed a murder was still within the ministry of God, since the law makes this statement regarding him: “God delivered him into his hands.” His hands therefore served as an instrument of divine punishment. The Levite is then the minister who remits, whereas the man who (in the example just cited) unwittingly and unwillingly struck another in a homicidal act became in fact an administrator of divine punishment. See to it that Christ is infused into the act of slaying an impious man and that sanctification accompany and be part of your attempt to abolish what is abominable. .
For there was a command under the law that cities of refuge should be appointed, in order that they who were sought after to be put to death might at least have some means of saving themselves. And when he who spoke to Moses, the Word of the Father, appeared in the end of the world, he also gave this commandment, saying, “But when they persecute you in this city, flee into another.”
God. When a person was slain undesignedly, the Providence of God was to be adored in silence, as nothing happens without his permission. (Haydock) See Numbers xxv. 6.