Here is, I. An alteration made in the computation of the effective men of the Levites - that whereas, in Moses's time, they were not enlisted, or taken into service, till they were thirty-years old, nor admitted as probationers till twenty-five (Num 8:24), David ordered, by direction from God, that they should be numbered for the service of the house of the Lord, from the age of twenty years and upwards, Ch1 23:24. This order he confirmed by his last words, Ch1 23:27. When he put his last hand to the draught of this establishment he expressly appointed this to be done for ever after; yet not he; but the Lord. 1. Perhaps the young Levites, having no work appointed them till twenty-five years old, had many of them got a habit of idleness, or grew addicted to their pleasures, which proved both a blemish to their reputation and a hindrance to their usefulness afterwards, to prevent which inconvenience they are set to work, and brought under discipline, at twenty-years old. Those that will be eminent must learn to take care and take care betimes. 2. When the work of the Levites was to carry burdens, heavy burdens, the tabernacle and the furniture of it, God would not call any to it till they had come to their full strength; for he considers our frame, and, in service as well as sufferings, will lay no more upon us than we are able to bear. But now God had given rest to his people, and made Jerusalem his dwelling-place for ever, so that there was no more occasion to carry the tabernacle and the vessels thereof, the service was much easier, and what would not over-work them nor over-load them if they entered upon it at twenty-years old. 3. Now the people of Israel were multiplied, and there was a more general resort to Jerusalem, and would be when the temple was built, than had ever been at Shiloh, or Nob, or Gibeon; it was therefore requisite there should be more hands employed in the temple-service, that every Israelite who brought an offering might find a Levite ready to assist him. When more work is to be done it is a pity but there should be more workmen fetched in for the doing of it. When the harvest is plenteous why should the labourers be few? II. A further account of the Levites' work. What the work of the priests was we are told (Ch1 23:13): To sanctify the most holy things, to burn incense before the Lord, and to bless in his name; that work the Levites were not to meddle with, and yet they had work enough, and good work, according to that to which they were appointed, Ch1 23:4, Ch1 23:5. 1. Those of them that were to set forward the work of the house of God (Ch1 23:4) were therein to wait on the sons of Aaron (Ch1 23:28), were to do the drudgery-work (if any work for God is to be called drudgery) of the house of God, to keep the courts and chambers clean, set things in their places, and have them ready when there was occasion to use them. They were to prepare the show-bread which the priests were to set on the table, to provide the flour and cakes for the meat-offerings, that the priests might have every thing ready to their hands. 2. Those of them that were judges and officers had an eye particularly upon all measure and size, Ch1 23:29. The standards of all weights and measures were kept in the sanctuary; and the Levites had the care of them, to see that they were exact, and to try other weights and measures by them when they were appealed to. 3. The work of the singers was to thank and praise the Lord (Ch1 23:30), at the offering of the morning and evening sacrifices, and other oblations on the sabbaths, new moons, etc., Ch1 23:31. Moses appointed that they should blow with trumpets over their burnt offerings and other sacrifices, and on their solemn days, Num 10:10. The sound of the trumpet was awful, and might be affecting to the worshippers, but was not articulate, nor such a reasonable service as this which David appointed, of singing psalms on those occasions. As the Jewish church grew up from its infancy, it grew more and more intelligent in its devotions, till it came at length, in the gospel, to put away childish things, Co1 13:11; Gal 4:3, Gal 4:9. 4. The work of the porters (Ch1 23:5) was to keep the charge of the tabernacle and of the holy place, that none might come nigh but such as were allowed, and those no nearer than was allowed them, Ch1 23:32. They were likewise to keep the charge of the sons of Aaron, to be at their beck and go on their errands, who are yet called their brethren, to be a memorandum to the priests that, though they were advanced to a high station, yet they were hewn out of the same rock with common Levites, and therefore must not lord it over them, but in all instances treat them as brethren.