1 Corinthians 9:13 - Clarke's commentary and critical notes on the Bible

Do ye not know that they which minister about holy things live of the things of the temple? and they which wait at the altar are partakers with the altar? They which minister about holy things - All the officers about the temple, whether priests, Levites, Nethinim, etc., had a right to their support while employed in its service. The priests partook of the sacrifices; the others had their maintenance from tithes, first fruits, and offerings made to the temple; for it was not lawful for them to live on the sacrifices. Hence the apostle makes the distinction between those who minister about holy things and those who wait at the altar.