Is it obligatory to cease eating and drinking (Imasak) for one who breaks the fast without a valid excuse?
General Chapter
Al-Mughni
Book of Fasting
Primary text
It is obligatory to cease eating and drinking for every person who must fast and breaks it without a valid excuse. This applies to one who breaks the fast intentionally, one who breaks it believing dawn has not yet appeared when it has, one who breaks it believing sunset has not yet occurred when it has not, and one who forgot to make the intention for fasting. There is no known disagreement on this ruling among the scholars.
Supporting text
There is a solitary opinion attributed to 'Ata' that permits breaking the fast for the remainder of the day for one who breaks it with an excuse, reasoning by analogy to his view regarding when evidence of the new moon sighting is established. However, this opinion is exceptional and has not been followed by the people of knowledge.