'Ark of the Covenant' in the Bible

At that time, did Yahweh separate the tribe of Levi, to bear the ark of the covenant of Yahweh, - to stand before Yahweh to wait upon him and to bless in his name (until this day).

And Moses wrote this law, and delivered it unto the priests the sons of Levi, who were bearing the ark of the covenant of Yahweh, - and unto all the elders of Israel.

then Moses commanded the Levites, who were bearing the ark of the covenant of Yahweh, saying:

Take this scroll of the law, and put it at the side of the ark of the covenant of Yahweh your God, - so shall it be there in thy midst as a witness.