from thirty years and above, even to fifty years, of all who enter to the office of their ministry and to the service of the covenant of the testimony
Other versions
King James Version
From thirty years old and upward even unto fifty years old shalt thou number them, every one that entereth into the service, to do the work of the tabernacle of the congregation. English Standard Version
From thirty years old up to fifty years old, you shall list them, everyone who can come on duty, to do the service of the tent of meeting.New International Version
Count all the men from thirty to fifty years of age who come to serve in the work at the Tent of Meeting.