The apostle Paul gives the best comment upon this passage, and indeed the subject in general: He that waiteth at the altar should be partaker of the altar. 1 Corinthians 9:1-14. I would only observe upon it, that as the LORD himself hath undertaken by this precept to provide for his servants, bad must be the mind that refuseth to comply: and, on the other hand, most unworthy must be that servant, who takes advantage of this, to exact from his brethren more than what is just and right.
Related Commentaries of Deuteronomy 18:4
Deuteronomy 18:4-5
4 The firstfruit also of thy corn, of thy wine, and of thine oil, and the first of the fleece of thy sheep, shalt thou give him.
5 For the LORD thy God hath chosen him out of all thy tribes, to stand to minister in the name of the LORD, him and his sons for ever.