Numbers 18:2-5

ECB(i) 2 and also your brothers of the rod of Levi, the scion of your father, oblate with you: they join to you and minister to you: and you, with your sons at the face of the tent of witness: 3 and they guard your guard and the guard of all the tent: only they approach not the instruments of the holies and the sacrifice altar so that they not die - neither they, nor you: 4 and they join you and guard the guard of the tent of the congregation, for all the service of the tent so that no stranger approaches you: 5 and guard the guard of the holies and the guard of the sacrifice altar so that there be no more rage on the sons of Yisra El.