From thirty years old and upward until fifty years old shall you number them; all that enter in to perform the service, to do the work in the tabernacle of meeting.
This is what pertains to the Levites: from twenty and five years old and upward they shall go in to wait upon the service of the tabernacle of meeting:
But shall minister with their brethren in the tabernacle of meeting, to keep the charge, and shall do no service. Thus shall you do unto the Levites regarding their duties.