Deuteronomy 18:6

“And if a Levite come from any of thy gates out of Israel, where he sojourned, etc.] In any of the cities through the land, for they were dispersed all over the country, and employed in instructing and teaching the people; and, excepting the cities which were given them to dwell in out of the various tribes, they were but sojourners: and come with all the desire of his mind unto the place which the Lord shall choose; the city of Jerusalem, where the temple would be built, and sacrifices offered, at which the Levites were assisting to the priests, and in various parts of the service of the sanctuary; and to which they are supposed to come with an hearty good will, with great eagerness of soul,…”

“if a Levite . . . come with all the desire of his mind--It appears that the Levites served in rotation from the earliest times; but, from their great numbers, it was only at infrequent intervals they could be called into actual service. Should any Levite, however, under the influence of eminent piety, resolve to devote himself wholly and continually to the sacred duties of the sanctuary, he was allowed to realize his ardent wishes; and as he was admitted to a share of the work, so also to a share of the remuneration. Though he might have private property, that was to form no ground for withholding or even diminishing his claim to maintenance like the other ministering priests. The reason or…”

“These verses presuppose that part of the Levites only will be in residence and officiating at the place of the sanctuary, the others of course dwelling at their own homes in the Levitical cities, or “sojourning” elsewhere; compare the marginal references. But if any Levite out of love for the service of the sanctuary chose to resort to it when he might reside in his own home, he was to have his share in the maintenance which was provided for those ministering in the order of their course. Deuteronomy 18:8 Beside that which cometh of the sale of his patrimony - The Levites had indeed “no part nor inheritance with Israel,” but they might individually possess property, and in fact often did so…”

“With all the desire of his mind - With full purpose to fix his abode, and to spend his whole time and strength in the service of God. It seems, the several priests were to come from their cities to the temple by turns, before David's time; and it is certain they did so after it. But if any of them were not contented with this attendance upon God in his tabernacle, or temple, and desired more entirely and constantly to devote himself to God's service there, he was permitted so to do, because this was an eminent act of piety joined with self - denial, to part with those great conveniences which he enjoyed in the city of his possession. Deuteronomy 18:8”

“come: Num 35:2, Num 35:3 and come with: Psa 26:8, Psa 27:4, Psa 63:1, Psa 63:2, Psa 84:5, Psa 84:10; Ti1 3:1; Pe1 5:2 unto the place: Deu 12:5, Deu 16:2 Deuteronomy 18:7”