The Madinan Period, Part 3: The Covenant, the Qiblah, and the Meaning of Jihad
Section 10 of 26 · The Life of the Prophet Muhammad: The Madinan Period
The Fast of Ramaḍān Is Prescribed
Finally, the ruling of fasting was in the second year of the hijrah. Allah (swt) revealed the ayah in Sūrat al-Baqarah:
يَـٰٓأَيُّهَا ٱلَّذِينَ ءَامَنُوا۟ كُتِبَ عَلَيْكُمُ ٱلصِّيَامُ كَمَا كُتِبَ عَلَى ٱلَّذِينَ مِن قَبْلِكُمْ لَعَلَّكُمْ تَتَّقُونَ
“O you who believe, the fasts have been enjoined upon you as they were enjoined upon those before you, so that you may be God-fearing,” (2:183)
So the purpose, or the wisdom, behind fasting is taqwā, so that believers may become righteous.