Whoever is Fasting and then Eats, Drinks or has Sexual Intercourse Forgetfully in Ramadān
Abu Hurayrah (radiyallāhu ‘anhu) narrated that the Prophet (salallāhu ‘alaihi wasallam) said: “Whoever is fasting and he forgets, so he eats or drinks, let his continue and complete his fast for it was Allah who fed him and gave him drink.”
And, in a narration, the Messenger (salallāhu ‘alaihi wasallam) said: “Whoever broke his fast in Ramadan forgetfully, there is no need for him to make it up (qadā) and no need for an expiation (kaffārah).”
Eating and drinking deliberately breaks the fast that is proven by the Book, Sunnah and ijmā’ and likewise, sexual intercourse breaks the fast. However, the one who eats or drinks forgetfully, then his fast is not affected according to these authentic narrations, and due to the statement of Allah (the Most High):
رَبَّنَا لَا تُؤَاخِذْنَا إِن نَّسِينَا أَوْ أَخْطَأْنَا
“Our Lord! Punish us not if we forget or fall into error.” And the Messenger (salallāhu ‘alaihi wasallam) stated: “Allah has overlooked the unintentional mistakes of my Ummah and what they forget, and what they are forced to do.”
The stated that, “it was Allah who fed him and gave him drink” so, it was not out of choice. The fast is nullified if a person eats and drinks deliberately. Furthermore, there is no kaffārah (penalty) or qadā (making up the fast).
Likewise, is the case for sexual intercourse that takes place out of forgetfulness, based on the same principle.
 Al-Bukhāri (no. 1933), Muslim (no. 1155).
 Reported by Al-Hākim (1/430) who said: “It is sahīh upon the conditions of Muslim” and Ad-Dhahabi agreed.
 Al-Baqarah: 286.
 Ibn Mājah (no. 2045) and authenticated by Ibn Hibbān (7219).
 See Tas’hīl Al-Ilmān of Shaikh Al-Fawzān, 3/226.