Deuteronomy 4:11-14

And ye came near and stood under the mountain; and the mountain burned with fire unto the heart of heaven, with darkness, cloud, and thick darkness. And Jehovah spake unto you out of the midst of the fire: ye heard the voice of words, but ye saw no form; only ye heard a voice. And he declared unto you his covenant, which he commanded you to perform, even the ten commandments; and he wrote them upon two tables of stone. And Jehovah commanded me at that time to teach you statutes and ordinances, that ye might do them in the land whither ye go over to possess it.