And the Lord spake unto Moses,.... And not unto Aaron, because a tithe out of the tithe was to be given to Aaron, as Aben Ezra observes, and it was not so proper that he should have this order to deliver to the Levites, in which he and his sons were so much concerned, and therefore it was given to Moses to acquaint them of it:

saying; as follows.

Appropriation of the Tithe. - Numbers 18:26. When the Levites took (received) from the people the tithe assigned them by Jehovah, they were to lift off from it a heave-offering for Jehovah, a tithe of the tithe for Aaron the priest (i.e., for the priesthood; see at Numbers 18:20). "Your heave-offering shall be reckoned to you as the corn of the threshing-floor, and the fulness (see Exodus 22:28) of the wine-press," i.e., according to Numbers 18:30, as the revenue of the threshing-floor and wine-press; that is to say, as corn and wine which they had reaped themselves.

And the LORD spake unto Moses, saying,

18:20-32 As Israel was a people not to be numbered among the nations, so Levi was a tribe to be distinguished from the rest. Those who have God for their Inheritance and their Portion for ever, ought to look with holy contempt and indifference upon the possessions of this world. The Levites were to give God his dues out of their tithes, as well as the Israelites out of their increase. See, in ver. 31, the way to have comfort in all our worldly possessions, so as to bear no sin by reason of them. 1. We must be sure that what we have is got honestly and in the service of God. That meat is best eaten which is first earned; but if any will not work, neither shall he eat, 2Th 3:10. 2. We must be sure that God has his dues out of it. We have the comfort of our substance, when we have honoured the Lord with it. Ye shall bear no sin by reason of it, when ye have heaved the best from it. We should give alms of such things as we have, that all may be holy and comfortable to us.