The story of the Israelites worshipping a Golden Calf, and Moses receiving the tablets of the Law is recounted in the Old Testament (Exodus 19, 20, 32: 1-24, 37).
Moses climbed Mount Sinai to receive the Ten Commandments of God's Law. While he was away the Israelites asked Aaron (who is dressed in white in Poussin's version of the event) to provide them with idols to worship. He cast from their gold ornaments a calf which was placed upon an altar and they worshipped it. When Moses returned he was so enraged by their actions that he smashed the tablets upon which the Commandments were inscribed (see Poussin's 'Adoration of the Golden Calf').