Matthew Poole and continuators on Joel 1:9

9 The meat-offering and the drink-offering is cut off from the house of the LORD ; the priests the LORDS ministers mourn .

Which by divine appointment was to be of fine Flower, Oyl and Frankincense, as Lev. 2.1. &c. and 6.14. &c. This meat-offering was necessary to every Sacrifice offered under the Law; so that without the Mincha, or meat-offering, the Sacrifice was maimed and illegal.

Required daily, as appears Exod. 29.40, 41. and Numb. 28.8. a fourth part of a hin of wine, for one lamb, Numb. 28.7.

By the destruction of the vines, by the locusts forementioned, all that wine (out of which they ought to offer the drink-offering) did fail.

It was to be poured out if Wine, and part of the meat-offering was to be burnt on the Altar, so both were disposed according to the Law, in the house of the Lord.

Sons of Aaron, with the Levites,

who did serve the Lord in the services of the Temple.

Grieve inwardly, and express it by outward signs, these had more cause then others to mourn, for as they had equal cause with others in respect to God, whose service hereby failed, so the Priests, in respect to their private gain and maintenance had more cause to mourn, their provision was by this means shortened.