Numbers 18:28-30

New International Version - UK

²⁸ In this way you also will present an offering to the Lord from all the tithes you receive from the Israelites. From these tithes you must give the Lord’s portion to Aaron the priest. ²⁹ You must present as the Lord’s portion the best and holiest part of everything given to you.”

³⁰ ‘Say to the Levites: “When you present the best part, it will be reckoned to you as the product of the threshing-floor or the winepress.