558 – Abu Hurayrah (may Allah be pleased with him) reported that the Messenger of Allah (peace and blessings be upon him) said: “Whoever is overtaken by vomiting is not required to make up the fast, but whoever deliberately induces vomiting must make it up.” Reported by the Five; Ahmad considered its chain defective, whereas al-Daraqutni upheld its soundness (1).

Hadith grading
The hadith is judged ḥasan. Al-Tirmidhi graded it ḥasan, while Ibn Ḥibbān and al-Ḥakim declared it authentic and al-Dhahabi concurred. Al-Daraqutni and ʿAbd al-Ḥaqq said, “All of its transmitters are trustworthy.” Others weakened it: al-Bukhari remarked, “I do not deem it preserved,” Imam Ahmad rejected it, and al-Tirmidhi concluded, “Nothing in this chapter is rigorously authentic.”

Glossary of the hadith
• dharaʿahu al-qayʾ – with three fatḥahs: the vomit preceded, overpowered, and forced itself out of him; compare the expression ḍāqa dharʿī (“my ability proved too narrow”), i.e., my strength failed. Al-qayʾ: whatever the stomach expels.
• istaqā – to seek to bring up vomit intentionally, by one’s own choice.

Points gleaned from the two hadiths

1. Both narrations show that eating, drinking, or vomiting deliberately, while aware and acting by choice, breaks the fast and invalidates it. This is the consensus of Muslim scholars, for fasting is defined as abstaining from nullifiers during a specified time span.
2. Eating or drinking out of forgetfulness does not invalidate the fast, nor is the fasting person deemed to have broken it. The Prophet’s words “let him complete his fast” prove that a valid fast remains, and the same meaning is confirmed by his statement