Have we got the Ten Commandments wrong? Why does this ancient copy look different from what we've been taught?

Wait, what? The Ten Commandments have another commandment? The oldest known surviving stone tablet of the Ten Commandments has been auctioned off in California.
An auction house in Beverly Hills has sold a national treasure of Israel for $850,000. The artifact is a two-foot square stone inscription of the Ten Commandments. It weighs about 115 pounds and is dated to the 400 and 600s AD.
The tablet was released by the Israeli Antiquities Authorities to be sold in the U.S. on the condition that it is to be displayed in a museum. It likely hung at the entrance of a synagogue.
The tablet is the oldest surviving example of the Ten Commandments in stone.
Curiously, the tablet contains just nine of the ten commandments we know about. The prohibition against taking the Lord’s name in vain is not on the tablet. Instead, there is a commandment instructing the people to raise a temple on Mount Gerizim.
The mountain is a holy place to the Samaritan people who inscribed the tablets. The switch in commandments was unique to their faith community.
The tablet was put up for $300,000 and sold for $850,000. It will be displayed in a museum as a stipulation of its sale.
By Marshall Connolly