23 And the LORD spoke unto Moses, saying, 24 This regarding the Levites from twenty-five years old and upward, they shall go in to serve in the host of the tabernacle of the testimony. 25 And from the age of fifty years they shall return from their ministry unto the host and shall never serve again, 26 but shall serve with their brethren in the tabernacle of the testimony, to stand guard, even though they do not serve in the ministry. Thus shalt thou do unto the Levites touching their charge.