Joshua 21:40
So all the cities for the children of Merari by their families, which were remaining of the families of the Levites, were by their lot twelve cities. So all the cities for the children of Merari by their families, which were remaining of the families of the Levites, were by their lot twelve cities.
The Merarite families, as those remaining of the families of the Levites, received twelve cities assigned to them by lot. Those twelve were part of a larger total of forty-eight cities scattered throughout the land. They were given in this scattered form because Levi received no separate territorial inheritance like the other tribes. The scattering of Levi had originally been pronounced as a curse, but it was turned into a blessing when the Levites remained faithful to Jehovah while the other tribes apostatized. Because of that faithfulness they were appointed to the sacred service of the sanctuary, so their dispersion became the means of ministry rather than punishment.