Deuteronomy 19:7-9

New International Version - UK

⁷ This is why I command you to set aside for yourselves three cities.

⁸ If the Lord your God enlarges your territory, as he promised on oath to your ancestors, and gives you the whole land he promised them, ⁹ because you carefully follow all these laws I command you today – to love the Lord your God and to walk always in obedience to him – then you are to set aside three more cities.