“These were the sons of Levi by their ancestral houses. These were the heads of fathers as they were enrolled according to the number of the names of the individuals from twenty years old and upward who were to do the work for the service of the house of Yahweh. King David said. ‘Yahweh, the God of Israel, has given rest to his people. He resides in Jerusalem forever. Thus the Levites no longer need to carry the tabernacle or any of the things for its service.’ According to the last words of King David, these were the number of the Levites from twenty years old and upward. However, their new duty shall be to assist the descendents of Aaron in the service of the house of Yahweh, having the care of the courts and the chambers, the cleansing of all that is holy, and any work for the service of the house of God. They were to assist also with the rows of bread, the choice flour for the grain offering, the wafers of unleavened bread, the baked offering, the offering mixed with oil, and all measures of quantity or size. They shall stand every morning, thanking and praising Yahweh, and likewise at evening. They shall do likewise whenever burnt offerings are offered to Yahweh on the Sabbath, new moons, and appointed festivals, according to the number required of them, regularly before Yahweh. Thus they shall keep charge of the tent of meeting and the sanctuary. They shall attend the descendents of Aaron, their kindred, for the service of the house of Yahweh.”
Here are the specific duties of the Levites. King David took some kind of census among the Levites. This is something that Yahweh frowned upon earlier in chapter 21. At the beginning of this chapter the number of Levites was 36,000 over the age of 30. Here the Levites are only 20 years old instead of 30. The duties in Numbers are no longer required because the Ark of the Covenant of Yahweh will be permanently in Jerusalem. The Levites have new duties to assist the descendents of Aaron. They were to take care of the courts and the chambers around the house of God. They were to clean the holy vessels. There were many specific duties. They were to be like the bakers of the Temple, preparing the breads, the flour, the use of oil, and the grain offerings. They were in charge of measuring the correct quantity. Every morning and every evening, they would thank and praise Yahweh. They will praise and thank Yahweh whenever burnt offerings are sacrificed. Whenever there is a festival, the Sabbath, or a new moon, they are the ones to thank and praise Yahweh. They were in charge of the tent and the sanctuary. This kind of work for many Christians is still being done by nuns and monks or priests, who do the praying for the rest of the community.