Sayyiduna Mu'adh bin Jabal (may Allah be pleased with him) narrates that the obligation of prayer was established in three stages, and the obligation of fasting was also established in three stages. The stages of prayer are as follows: When the Noble Prophet (peace and blessings be upon him) migrated to Madinah Munawwarah, he (peace and blessings be upon him) used to pray facing Bayt al-Maqdis for seventeen months... (The complete hadith has already been mentioned in the Book of Prayer.) The stages of fasting are as follows: When the Messenger of Allah (peace and blessings be upon him) migrated to Madinah Munawwarah, he (peace and blessings be upon him) used to fast three days every month. Yazid, the narrator, says: From Rabi' al-Awwal until the obligation of fasting in the month of Ramadan, for a total of seventeen months, he (peace and blessings be upon him) used to fast three days every month. He (peace and blessings be upon him) also fasted on the tenth of Muharram. Then Allah Almighty made the fasting of the month of Ramadan obligatory upon him (peace and blessings be upon him) and revealed these verses: {یَا اَیُّہَا الَّذِیْنَ آمَنُوا کُتِبَ عَلَیْکُمُ الصِّیَامُ کَمَا کُتِبَ عَلَی الَّذِیْنَ مِنْ قَبْلِکُمْ لَعَلَّکُمْ تَتَّقُوْنَ۔} (O you who believe! Fasting is prescribed for you as it was prescribed for those before you, so that you may become righteous.) And He said: { وَعَلَی الَّذِیْنَیُطِیْقُوْنَہُ فِدْیَۃٌ طَعَامُ مِسْکِیْنٍ} (And for those who can fast with difficulty, they have [the option] to feed a poor person [as a ransom] .) Acting upon these verses, whoever wished would fast, and whoever did not wish to fast would feed a poor person as ransom, and that would suffice for him. After that, Allah Almighty revealed this command: {شَہْرُ رَمَضَانَ الَّذِی اُنْزِلَ فیِہِ الْقُرْآنُ ھُدًی لِّلنَّاسِ وَبَیِّنَاتٍ مِّنَ الْھُدٰی وَالْفُرْقَانِ فَمَنْ شَہِدَ مِنْکُمُ الشَّہْرَ فَلْیَصُمْہُ} (The month of Ramadan is that in which the Qur'an was revealed, a guidance for mankind and clear proofs of guidance and criterion. So whoever of you sights [the crescent of] the month, let him fast it.) In this way, Allah Almighty made fasting in this month obligatory upon every resident and healthy person, but gave concession to the sick and the traveler to not fast, and for the elderly who could not bear fasting, the ruling remained that they should feed a poor person as ransom. These are two conditions. The third condition was that people could eat, drink, and have relations with their wives until they slept at night, but after sleeping, all this became forbidden for them. One day, it happened that an Ansari Companion named Surmah worked all day while fasting. When evening came, he reached home, prayed the 'Isha prayer, and slept without eating or drinking, until morning came and thus his fast had already begun. When the Messenger of Allah (peace and blessings be upon him) saw him and noticed that he was very exhausted, he (peace and blessings be upon him) asked him: "You look very exhausted, what is the reason?" He said: "O Messenger of Allah! I worked all day yesterday, and when I came home and lay down, I fell asleep (and thus eating and drinking became forbidden for me), and when morning came, I had to remain fasting." On the other hand, Sayyiduna 'Umar bin Khattab (may Allah be pleased with him) also had an incident that after waking up from sleep, he had relations with his wife or slave woman, and he came to the Messenger of Allah (peace and blessings be upon him) and told him the whole matter. At that time, Allah Almighty revealed this command: {اُحِلَّ لَکُمْ لَیْلَۃَ الصِّیَامِ الرَّفَثُ إلَی نِسَائِکُمْ ھُنَّ لِبَاسٌ لَّکُمْ وَاَنْتُمْ لِبَاسٌ لَّھُنَّ عَلِمَ اللّٰہُ اَنَّکُمْ کُنْتُمْ تَخْتَانُوْنَ اَنْفُسَکُمْ فَتَابَ عَلَیْکُمْ وَعَفَا عَنْکُمْ فَالْئٰنَ بَاشِرُوْھُنَّ وَابْتَغُوْا مَا کَتَبَ اللّٰہُ لَکُمْ وَکُلُوْا وَاشْرَبُوْا حَتّٰییَتَبَیَّنَ لَکُمُ الْخَیْطُ الْاَبْیَضُ مِنَ الْخَیْطِ الْاَسْوَدِ مِنَ الْفَجْرِ ثُمَّ اَتِمُّوْا الصِّیامَ إِلَی الَّیْلِ۔} (It has been made lawful for you to have relations with your wives on the nights of fasting. They are a garment for you and you are a garment for them. Allah knows that you used to deceive yourselves, so He accepted your repentance and forgave you. So now, have relations with them and seek what Allah has decreed for you. And eat and drink until the white thread of dawn becomes distinct to you from the black thread [of night] . Then complete the fast until the night.)