Deuteronomy 10:1-5 At that time the LORD said unto me, Hew thee two tables of stone like unto the first, and come up unto me into the mount, and make thee an ark of wood. 2 And I will write on the tables the words that were in the first tables which thou brakest, and thou shalt put them in the ark. 3 And I made an ark of shittim wood, and hewed two tables of stone like unto the first, and went up into the mount, having the two tables in mine hand. 4 And he wrote on the tables, according to the first writing, the ten commandments, which the LORD spake unto you in the mount out of the midst of the fire in the day of the assembly: and the LORD gave them unto me. 5 And I turned myself and came down from the mount, and put the tables in the ark which I had made; and there they be, as the LORD commanded me.
Hebrews 9:4 Which had the golden censer, and the ark of the covenant overlaid round about with gold, wherein was the golden pot that had manna, and Aaron’s rod that budded, and the tables of the covenant;
A simple term for the Ark of the Covenant is, “a box to carry the covenant.” That was its entire purpose. Jesus asked, “which is greater the gold or the temple which sanctifies the gold?” A long these same lines, which is more important the box itself or the covenant inside it? Remove the Ten Commandments and all that is left is a fancy box covered in fine gold. The Ark of the Covenant was created to bring emphasis and added significance to the covenant which was inside it i.e. The Ten Commandments.
Moses, after forty days in the mount, comes down And he was there with the Lord forty days and forty nights; he did neither eat bread, nor drink water. And he wrote upon the tables the words of the covenant, the ten commandments. Exodus 34:28
And he declared unto you his covenant, which he commanded you to perform, even ten commandments; and he wrote them upon two tables of stone. Deuteronomy 4:13.
Regarding the Ark of the Covenant in Revelation 11:18. Angels do not marry (Matthew 22:30), neither do they have children, which in turn means they do not have parents. Therefore the law in Heaven cannot be the Ten Commandments in a literal sense, because there is no need to command angels to honor their fathers and mothers. The law in heaven is simply to love God and to love one another. Christ said these two commandments are the greatest of all of God’s commandments in the Bible; which means they are greater than even the Decalogue! And rightly so, since this is the “Law of Christ” that is written in our hearts by the Holy Spirit (John 15:12 Galatians 6:2), under the New Covenant, and is the law for all of God’s Kingdom, both on earth and in heaven.