1 Corinthians 9:13
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?
Note 10 at 1Co 9:13: Paul was referring to the Old Testament sacrificial system in which the priests and the Levites served. The phrase "wait at the altar" denotes a continual service in which a portion of the offering was shared with those ministering at the altar. The priests' and Levites' food was supplied for them as a part of their livelihood (Le 7:6-10, 14, 28-36; Nu 18:8, 31; and De 18:1-4).