'Ark' in the Bible
Their duties pertained to the ark, the table, the lamp stand, the altars, the utensils of the sanctuary with which they ministered, and all the curtains in use.
When the camp is about to travel, Aaron and his sons are to come and take down the veil of the curtain and cover the Ark of the Testimony with it.
When Moses entered the Tent of Meeting to speak with the L ORD, he heard a voice speaking to him above the Mercy Seat over the Ark of the Testimony. He spoke to him from between the two cherubim.
So they traveled from the mountain of the LORD, a three-day trip, with the Ark of the Covenant of the LORD traveling in front of them a three day trip to explore a place for them to rest.
Whenever the ark was ready to travel, Moses would say: "Arise, LORD, to scatter your enemies, so that whoever hates you will flee from your presence."
Whenever the ark was being readied to rest, he would say: "Return, LORD, to the countless thousands of Israel."
But they presumed to go up to the top of the mountain, even though the Ark of the Covenant of the LORD and Moses didn't leave the camp.
"Then lay them there in the Tent of Meeting in front of the Ark of the Covenant where I'll meet with you.