CLV(i)
24 This is what applies to the Levites. From twenty-five years old and upward may one come to enlist with the Levitical host in the service of the tent of appointment.
25 And from fifty years old shall one retire from the active service in the Levitical host and shall serve no longer;
26 yet he may minister to his brothers in the tent of appointment, so as to keep guard, though in active service he shall not serve. Thus shall you deal with the Levites in regard to their charges.