So Moses cried out to the Lord, and the Lord showed him a tree. When Moses threw the tree into the water, the water became good to drink. There the Lord gave the people a rule and a law to live by, and there he tested their loyalty to him.
Moses said this about the people of Levi: “Lord, your Thummim and Urim belong to Levi, whom you love. Lord, you tested him at Massah and argued with him at the waters of Meribah.
Remember how the Lord your God has led you in the desert for these forty years, taking away your pride and testing you, because he wanted to know what was in your heart. He wanted to know if you would obey his commands.