Deuteronomy 19:4-5
Read this passage and open each verse for the full verse feed and commentary tools.
4And this is the case of the manslayer, that shall flee thither and live: whoso killeth his neighbor unawares, and hated him not in time past; 5as when a man goeth into the forest with his neighbor to hew wood, and his hand fetcheth a stroke with the axe to cut down the tree, and the head slippeth from the helve, and lighteth upon his neighbor, so that he dieth; he shall flee unto one of these cities and live:
Deuteronomy 19:4-5 (ASV)