Deuteronomy 9:17

Moses cast from him the two tables of stone on which God had inscribed the words of the Law, and broke them in pieces in the view of the people, when he came down from the mount and saw how they had turned aside from the right way, and were become idolaters. This was not the effect of a burst of indignation on his part; it was a solemn declaration that the covenant of God with his people had been nullified and broken by their sinful apostasy.