Numbers 8:22-26

Matthew(i) 22 And after that they went in, to do theyr seruyce in the tabernacle of wytnesse, before Aaron & hys sonnes. And acordyng as the Lord had commaunded Moses as concernyng the Leuites, euen so they dyd vnto them. 23 And the Lord spake vnto Moses saying: 24 thys shalbe the maner of the Leuites: from .xxv. yere vpwarde they shall go in to wayte vpon the seruice in the tabernacle of witnesse, 25 & at fyfty they shal ceasse waytyng vpon the seruyce therof, and shall laboure no moare: 26 but shal mynistre vnto their bretheren in the tabernacle of wytnesse, and there wayte, but shall do no moare seruyce. And se that thou do after thys maner vnto the Leuites in their waytyng tymes.