Sayyiduna Musa علیہ السلام read the rulings from Tawrah before the Bani Israel and instructed to abide by those rulings. When the Bani Israel heard the rulings of Tawrah, they straight away refused to accept these commandments. As a consequence of their disobedience, the Divine torment struck them in such a way that all of a sudden, the Mountain Sinai uprooted, flew and suspended in the air over the heads of the Bani Israel who were living in a land that was covering an area of three miles in length and three miles in width. When the Bani Israel saw that the mountain is hanging over their heads, they all fell into prostration and started promising that they have accepted all of the rulings of Tawrah and they would also act upon them. But at the time of prostration, they kept their cheek and left eye brow on the ground and were looking with the right eye at the mountain whether it is falling upon them or not. And this is for the same reason that even today the Jews prostrate in the similar manner that they keep their left cheek and left eyebrow on the ground.
Anyhow, when the Bani Israel repented and promised to comply with the rulings and commandments of Tawrah, then the mountain flew back and reset at its original place. The Holy Quran has described this event in few places. For example, in Surah Al-A’raf it is mentioned that:
And when We lifted the Mount (Sinai) above them as if it was a canopy, and they thought that it would fall upon them; accept firmly what We have given you, and remember what is in it, so that you may become pious.
[Kanz-ul-Iman (Translation of Quran)] (Part 9, Surah Al-A’raf, verse 171)
Moral: This event highlights that adopting strict methods and punitive techniques to make the sinful people act upon virtuous deeds or to make them accept a righteous commandment is proven from the tradition of Allah . (واللہ تعالٰی اعلم)