Matthew Poole and continuators on Joshua 21:3

3 And the children of Israel gave unto the Levites out of their inheritance , at the commandment of the LORD, these cities and their suburbs .

It seems most probable, that they gave to the Levites promiscuously such Cities as God commanded, and that the Lot appropriated them to their several Houses or Families.

i. e. Out of their several Possessions; partly, that the burden and loss might be equally divided; and principally, that the Levites being dispersed among the several Tribes, according to Iacobs Prediction, Gen. 49. 7. might more easily, and frequently, and effectually Teach the Israelites Gods Law and Iudgments, which they were engaged to do, Deut. 33. 10. and that the People might upon all occasions resort to them, and require the meaning of the Law at their mouths, Mal. 2. 7.

Not only the use, but the absolute Dominion of them, as is manifest both from v. 11, 12. where a distinction is made between the City and Suburbs of Hebr[illegible: 1+ letters], and the Fields and Villages thereof, and the former are given to the Levites, the latter to Caleb; and from the return of these Cities in the Iubilee, unto the Levites as to their proper owners, Levit. 25. 33, 34.