23 And the Lord spoke to Moses, saying:
24 This is the law of the Levites: From twenty-five years old and upwards, they shall go in to minister in the tabernacle of the covenant.
25 And when they shall have accomplished the fiftieth year of their age, they shall cease to serve:
26 And they shall be the ministers of their brethren in the tabernacle of the covenant, to keep the things that are committed to their care, but not to do the works. Thus shalt thou order the Levites touching their charge.