When Moses and the children of Israel were brought out of Egypt by God and on the way to the Promised Land, God called Moses to meet Him on Mt. Sinai. There God spoke with Moses and gave him laws that the people were to follow and sent him back to the children of Israel.
Moses had been gone on the mount so long that the people were afraid something had happened to him and had made themselves a golden calf and were worshipping it as their god. Moses was furious with the people. In anger he threw the tablets at his feet and broke them. He had to go back up on Mt. Sinai and face God. God threatened to not go with the people to the Promised Land; but Moses pleaded with God not to forsake them. God in His great mercy relented and rewrote the 10 Commandments for Moses.