Numbers 20:22-29

²²And the children of Israel, even the whole congregation, journeyed from Kadesh, and came unto mount Hor. ²³And the LORD spake unto Moses and Aaron in mount Hor, by the coast of the land of Edom, saying, ²⁴Aaron shall be gathered unto his people: for he shall not enter into the land which I have given unto the children of Israel, because ye rebelled against my word at the water of Meribah. ²⁵Take Aaron and Eleazar his son, and bring them up unto mount Hor: ²⁶And strip Aaron of his garments, and put them upon Eleazar his son: and Aaron shall be gathered unto his people, and shall die there. ²⁷And Moses did as the LORD commanded: and they went up into mount Hor in the sight of all the congregation. ²⁸And Moses stripped Aaron of his garments, and put them upon Eleazar his son; and Aaron died there in the top of the mount: and Moses and Eleazar came down from the mount. ²⁹And when all the congregation saw that Aaron was dead, they mourned for Aaron thirty days, even all the house of Israel.