The Bible describes the Ark as made of shittah-tree wood (acacia). It was 1.5 cubits broad and high, and 2.5 cubits long, conforming to the golden ratio. (~130 x 78 x 78 cm or 4.27 x 2.56 x 2.56 ft, using the Egyptian royal cubit). The Ark was covered with the purest gold, and its upper surface or lid, the mercy seat (Hebrew: כפורת, Kaporet), was surrounded with a rim of gold.
On each of the two long sides were two gold rings, which allowed two wooden poles (with a decorative sheathing of gold), to be placed within to allow the Ark to be carried (Num. 7:9; 10:21; 4:5,19, 20; 1 Kings 8:3, 6). Over the Ark, at the two extremities, were two cherubim, with their faces turned toward one another (Leviticus 16:2; Num. 7:89). Their outspread wings over the top of the Ark formed the throne of God, while the Ark itself was his footstool (Ex. 25:10-22; 37:1-9). The Ark was placed in the “Holy of Holies,” so that one end of the carrying poles touched the veil separating the two compartments of the tabernacle (1 Kings 8:8).
According to the Bible, the two tablets of stone constituting the Ten Commandments were kept within the Ark itself. A golden jar containing some of the manna from the Israelites’ trek in the wilderness, and the rod of Aaron that budded, were added to the contents of the Ark (Ex. 16:32-34; Heb. 9:4). However, these were apparently were later removed at some point prior to the building of Solomon’s temple, as I Kings 8:9 that there “was nothing in the Ark save the two tablets of stone.” While Heb. 9:4 states these items were placed “inside” the Ark, Ex. 16:33-34 and Num. 17:10 use the expression “before” the Ark; some see a contradiction here. However, none exists.
The original Greek word translated “wherein” in Hebrews 9:4 is HOU. From “Strong’s Exhaustive Concordance of the Bible” and other sources, we find that HOU means “at which place.” HOU is a general word which does not necessarily mean “wherein,” “within,” or “in.” It simply means “in the same location as.”
With this in mind, notice Deuteronomy 31:24-26: “And it came to pass, when Moses had made an end of writing the words of this law in a book [not the Ten Commandments which God had written on two tables of stone, but the civil law which Moses had written in a book — the law of Moses], until they were finished, That Moses commanded the Levites, which bare the ark of the covenant of the Lord, saying, Take this book of the law, and put it in the side of the ark of the covenant of the Lord your God, that it may be there for a witness against thee.”
Notice that the book of the law was not placed INSIDE the ark, but “in the side of” (“by the side of” RSV) the ark. That is why the book of the law is not mentioned in I Kings 8:9 as being in the ark. The book of the law, along with the pot of manna (Ex. 16:33-34) and Aaron’s rod, was kept by the side of the ark, not in it. All of these items could properly be described as being HOU — in the same place as — the ark.