Deuteronomy 19:11

“But if he did not lie in wait for him, but God let him fall into his hand, then I will appoint you a place to which he may flee.

“If, however, a man acts presumptuously toward his neighbor, so as to kill him by deceit, you shall take him even from My altar, that he may die.

then you shall select for yourselves cities to be your cities of refuge, that the manslayer who has struck down any person unintentionally may flee there.

‘And if he pushed him of hatred or threw something at him lying in wait and as a result he died,

Then Moses set apart three cities across the Jordan to the east toward the sunrise,

“Speak to the sons of Israel, saying, ‘Designate the cities of refuge, of which I spoke to you by the hand of Moses,

“For he took his life in his hand and struck the Philistine, and Yahweh brought about a great salvation for all Israel; you saw it and were glad. Why then will you sin against innocent blood by putting David to death without a cause?”