Deuteronômio 4:42

42 para que se acolhesse ali o homicida que matasse, involuntariamente, o seu próximo, a quem, dantes, não tivesse ódio algum, e se acolhesse a uma destas cidades e vivesse:

42 to which anyone who had killed a person could flee if they had unintentionally killed a neighbor without malice aforethought. They could flee into one of these cities and save their life.