557 – Abu Hurayrah (may Allah be pleased with him) reported that the Messenger of Allah (peace and blessings be upon him) said: “If someone forgets while he is fasting and eats or drinks, he must complete his fast, for it is Allah who has fed him and given him drink.” Agreed upon by al-Bukhari and Muslim.

Al-Hakim relates another wording: “Whoever breaks the fast in Ramadan out of forgetfulness is not required to make it up, nor is any expiation due.” This version is authentic (1).

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Hadith grading:
The hadith is ṣaḥīḥ. Al-Hakim narrated it and declared it sound. The author concurs, and Shaykh al-Albani adds: “The fourth narration, through Abu Salamah ibn ʿAbd al-Raḥmān from Abu Hurayrah, states: ‘Whoever breaks the fast in the month of Ramadan forgetfully, no make-up and no expiation are due.’ It was recorded by Ibn Ḥibbān (3521) and by al-Hakim, who authenticated it according to Muslim’s criteria; al-Dhahabi agreed. It was also transmitted by al-Daraqutni (2/178) and al-Bayhaqi (7863), both of whom said, ‘All of its transmitters are trustworthy.’ I say: its chain is ḥasan.”

Glossary of the hadith:
• fa-liyutim ṣawmahu (let him complete his fast): the lām is the imperative lām, and the mīm carries a fatḥah because the verb is doubled.
• fa-innamā: a clause explaining why the forgetful person is not deemed to have broken his fast; since sustenance comes directly from Allah and the servant has no contrivance in obtaining it, it is not attributed to him. Eating forgetfully is analogous, for the servant played no deliberate part in it.
• innamā: a particle of restriction meaning, “No one fed him or gave him drink except Allah,” indicating that forgetfulness comes from Allah and is a mark of His gentleness toward His servants.