Back 
Surah 2. Al-Baqara
Ayah 65 - 66
65وَلَقَدْ عَلِمْتُمُ ٱلَّذِينَ ٱعْتَدَوْا۟ مِنكُمْ فِى ٱلسَّبْتِ فَقُلْنَا لَهُمْ كُونُوا۟ قِرَدَةً خَـٰسِـِٔينَ
66فَجَعَلْنَـٰهَا نَكَـٰلًا لِّمَا بَيْنَ يَدَيْهَا وَمَا خَلْفَهَا وَمَوْعِظَةً لِّلْمُتَّقِينَ
[65-66] And you know well the story of those among you who broke Sabbath.82 We said to them, "Be apes83 despised and hated by all. Thus We made their end a warning to the people of their time and succeeding generations, and an admonition for God-fearing people.
82Sabbath: Saturday. The Israelites were enjoined to keep the Sabbath as "a sign between me and you throughout your generations" for a perpetual covenant. "Six days tray work be done; but in the seventh is the Sabbath of rest, holy to the Lord: whosoever death any work in the Sabbath day, he shall surely be put to death." (Exodus, 31: 12-17) But when the Israelites became corrupt morally and religiously. they began to desecrate it openly and began to do business without hesitation on the Sabbath.
83This incident has been described in detail in Al-A'raf, VII: There is a difference of opinion as to what actually happened. Some are of the opinion that they were physically transformed into apes, while others hold the view that from that time onward they began to behave like apes. The words of the Qur'an, however, indicate that it was not a moral but a physical metamorphosis. In my opinion their bodies were transformed into those of apes, but their human minds were left intact in order to subject them to extreme torture.