Numbers 18:27-29

Amplified Bible, Classic Edition

²⁷ And what you lift out and keep [your heave offering] shall be credited to you as though it were the grain of the threshing floor or as the fully ripe produce of the vine.

²⁸ Likewise you shall also present an offering to the Lord of all your tithes which you receive from the Israelites; and therefore you shall give this heave offering [lifted out and kept] for the Lord to Aaron the priest.

²⁹ Out of all the gifts to you, you shall present every offering due to the Lord, of all the best of it, even the hallowed part lifted out and held back out of it [for the Levites].