Most people know of Moses, who led the Israelites out of Egypt.  Moses led his people to the very edge of the Promised Land.  It was Joshua, Moses' aid who actually led the Israelites into the Promised Land.  After all of the struggles to get to the Promised Land, Joshua exhorts the people to serve the Lord, and Him alone.  The Israelites say that they will, but Joshua warns them that they must be true to their oath:

 And Joshua recorded these things in the Book of the Law of God.  Then he took a large stone and set it up there under the oak near the holy place of the Lord.  "See!" he said to all the people.  "This stone will be a witness against us.  It has heard all the words the Lord has said to us.  It will be a witness against you if you are untrue to your God."