John Calvin Commentary Numbers 35:1

"And Jehovah spake unto Moses in the plains of Moab by the Jordan at Jericho, saying," — Numbers 35:1 (ASV)

And the Lord spoke to Moses. Although no inheritance was assigned to the tribe of Levi, it was still necessary that they be supplied with dwelling places. No lands were given to them where they might sow and reap; but by way of compensation, the tithes were a sufficient means of subsistence, even after deducting the tithes that were paid to the poor.

God now, however, makes provision for their residences. Here we must carefully note that they were distributed over the whole land in such a way as to be, as it were, guards regularly stationed for the preservation of God’s worship, so that no superstition might creep in, or the people fall into gross contempt of God.

For we know that they were chosen by Him, not only to attend to the ceremonies, but also to be the interpreters of the Law and to foster sincere piety among the people. If all had been placed in one location, there was a danger that the doctrine of the Law would immediately fall into oblivion throughout the whole land, and thus the other tribes would become irreligious.

Therefore, the incomparable goodness of God shone forth here, since their punishment was turned, as it were, into a reward for virtue, and their disgrace into honor. For this dispersion of the tribe of Levi had been foretold by the holy patriarch Jacob (Genesis 46:7), that their posterity would be scattered in that land, which Levi, the father of their race, had polluted by a detestable murder and wicked treachery.

God eventually proved that this prophecy, which proceeded from Him, did not fall to the ground unfulfilled. Nevertheless, although the Levites were to be scattered here and there as a token of their disgrace, they were still placed in various parts of the land so that they might keep the other tribes under the yoke of the Law.

It was, then, by God’s wonderful providence that they were placed in distinct and fixed residences, rather than being allowed to mingle indiscriminately with the rest of the people. For the cities God assigned to them were like so many schools, where they could better and more freely engage in teaching the Law and prepare themselves for performing the office of teaching.

For if they had lived indiscriminately among the multitude, they would have been liable to contract many vices and to neglect the study of the Law. But when they were thus gathered into separate communities, such an association reminded them that they were set apart from the people so that they might devote themselves entirely to God.

Besides, their cities were like lamps shining into the very farthest corners of the land. They were therefore fortified, as it were, by walls, so that the corruptions of the people would not penetrate to them.

Their association together also should have stimulated them to mutually exhort each other to uphold decent and modest manners, temperance, and other virtues worthy of God’s servants. Meanwhile, if they fell into dissolute habits, they were all the less excusable.

Thus, their cities were like watchtowers in which they could keep guard, so as to drive impiety away from the borders of the holy land. From here the light of heavenly doctrine was diffused; from here the seed of life was scattered; from here examples of holiness and universal integrity were to be sought.