The Ark of the Covenant, also known as the Ark of the Testimony or the Ark of God, is an artifact believed to be the most sacred relic of the Israelites, which is described as a wooden chest, covered in pure gold, with an elaborately designed lid called the mercy seat. According to the Book of Exodus, the Ark contained the two stone tablets of the Ten Commandments. According to the New Testament Book of Hebrews, it also contained Aaron's rod and a pot of manna. The biblical account relates that approximately one year after the Israelites' exodus from Egypt, the Ark was created according to the pattern given to Moses by God when the Israelites were encamped at the foot of Mount Sinai. Thereafter, the gold-plated acacia chest was carried by its staves by the Levites approximately 2,000 cubits (approximately ) in advance of the people when on the march. God spoke with Moses "from between the two cherubim" on the Ark's cover. According to the Book of Exodus, God instructed Moses to build the Ark during his 40-day stay upon Mount Sinai. He was shown the pattern for the tabernacle and furnishings of the Ark, and told that it would be made of shittim wood (also known as acacia wood) to house the Tablets of Stone. Moses instructed Bezalel and Aholiab to construct the Ark. The Book of Exodus gives detailed instructions on how the Ark is to be constructed. It is to be cubits in length, cubits breadth, and cubits height (approximately ) of acacia wood. Then it is to be gilded entirely with gold, and a crown or molding of gold is to be put around it. Four rings of gold are to be attached to its four corners, two on each side—and through these rings staves of shittim wood overlaid with gold for carrying the Ark are to be inserted; and these are not to be removed. A golden lid, the kapporet (translated as or ), which is ornamented with two golden cherubim, is to be placed above the Ark. Missing from the account are instructions concerning the thickness of the mercy seat and details about the cherubim other than that the cover be beaten out over the ends of the Ark and that they form the space where God will appear.