The fields of the city, i.e. all beyond the 2000 cubits expressed Numbers 35:5. This is here mentioned, not as his peculiar case, but as one eminent instance, to show that it was so in all the rest of the cities here named; that the fields and villages thereof still belonged to the several tribes from whom the cities and their suburbs were taken; and to make the rest of the Israelites more contentedly and cheerfully resign so great a part of their possessions to the Levites, because even Caleb did so, though his possession had been long before promised, and now actually given to him by God's special command, as a mark of honour and compensation for his long and faithful service.
Related Commentaries of Joshua 21:12
Joshua 21:12
12 But the fields of the city, and the villages thereof, gave they to Caleb the son of Jephunneh for his possession.