Exodus 32:15-16, 19

Then Moses turned and went down from the mountain with the two tablets of the testimony in his hand, tablets that were written on both sides; on the front and on the back they were written. The tablets were the work of God, and the writing was the writing of God, engraved on the tablets.

And as soon as he came near the camp and saw the calf and the dancing, Moses’ anger burned hot, and he threw the tablets out of his hands and broke them at the foot of the mountain.