you shall count them from thirty years old and upward until fifty years old: all who enter in to wait on the service, to do the work in the Tent of Meeting.
“This is what is assigned to the Levites: from twenty-five years old and upward they shall go in to wait on the service in the work of the Tent of Meeting;
but shall assist their brothers in the Tent of Meeting, to perform the duty, and shall perform no service. This is how you shall have the Levites do their duties.”