Numbers 4:14

After this it is said what are the works of the sons of Kohath in the midst of the sons of Levi according to their peoples in the tabernacle of testimony. "Aaron," it says, "and his sons shall enter, when the camps are lifted up, and they shall take down the veil with which the holy things are covered, and they shall cover the ark of the testament with that very veil." And after this certain seven kinds are enumerated which are commanded to be covered. In the first place, that the ark of the testament itself, more precious than all, be covered with the veil by which it was formerly veiled, but also be covered over with a hyacinth-colored skin. Another covering too, hyacinth-colored, is added on top. In the second place the table is covered, in the third the candlestick, in the fourth the golden altar, in the fifth the vessels of ministry, in the sixth the covering of the altar is placed with certain veils, in the seventh place both the laver is covered, and none of all these is left naked or unveiled. Finally there is added also a precept of this kind: "Do not," it says, "exterminate the people of Kohath from their tribe"—namely, that they might know themselves to be about to be exterminated, if perchance they should put their hands to moving these things, unless each of them had first been covered over by the priests.