17. For all the first born of the children of Israel are mine, both man and beast: on the day that I smote every first-born in the land of Egypt I sanctified them for myself.
18. And I have taken the Levites for all the first-born of the children of Israel.
19. And I have given the Levites as a gift to Aaron and to his sons from among the children of Israel, to do the service of the children of Israel in the tabernacle of the congregation, and to make an atonement for the children of Israel: that there may be no plague among the children of Israel, when the children of Israel come nigh to the sanctuary.
20. And Moses, and Aaron, and all the congregation of the children of Israel, did to the Levites according to all that the LORD commanded Moses concerning the Levites, so did the children of Israel to them.
21. And the Levites were purified, and they washed their clothes; and Aaron offered them as an offering before the LORD; and Aaron made an atonement for them to cleanse them.
22. And after that went the Levites in to perform their service in the tabernacle of the congregation before Aaron, and before his sons: as the LORD had commanded Moses concerning the Levites, so did they to them.
23. And the LORD spoke to Moses, saying,
24. This is it that belongeth to the Levites: from twenty and five years old and upward they shall go in to wait upon the service of the tabernacle of the congregation:
25. And from the age of fifty years they shall cease waiting upon the service of it, and shall serve no more:
26. But shall minister with their brethren in the tabernacle of the congregation, to keep the charge, and shall do no service. Thus shalt thou do to the Levites concerning their charge.