Numbers 8:20-26 - The Levites Are Dedicated To The Lord
20 And Moses and Aaron and all the assembly of the sons of Israel did thus unto the Levites, - according to all that Yahweh commanded Moses as touching the Levites, so, did the sons of Israel unto them. 21 And the Levites accepted the cleansing from sin and washed their clothes, and Aaron offered them as a wave-offering before Yahweh, - and Aaron put a propitiatory-covering over them to make them pure. 22 And after that, went the Levites in to do their laborious work in the tent of meeting, before Aaron and before his sons, - as Yahweh commanded Moses concerning the Levites, so, did they unto them.
23 And Yahweh spake unto Moses saying; 24 This is what concerneth the Levites, - from twenty-five years old and upwards, shall they enter to take rank in the host, for doing the laborious work of the tent of meeting; 25 but from the age of fifty years, shall they retire from taking rank in the labour, and shall do laborious work no more; 26 yet shall they wait upon their brethren in the tent of meeting, by keeping charge, but laborious work, shall they not perform, - thus, shalt thou do unto the Levites, as touching their charges.