'Tablets' in the Bible

Nothing was in the ark except the two tablets that Moses had put in it at Horeb, where the Lord had made a covenant with the Israelites when they came out of Egypt.

So the king summoned Jehoiada the chief priest, and said to him, "Why have you not made the Levites collect from Judah and Jerusalem the tax authorized by Moses the Lord's servant and by the assembly of Israel at the tent containing the tablets of the law?"