Is excessive rinsing or sniffing while fasting disliked or invalidating?
General Chapter
Al-Mughni
Book of Fasting
Primary text
If a person exceeds three rinses/sniffs or is excessive in sniffing, they have performed a disliked act. This is supported by the Hadith where the Prophet, peace be upon him, advised Laqit ibn Sabra, 'And be thorough in sniffing, except when you are fasting' (Hadith is authentic). Performing the excessive action is disliked because it exposes one to causing water to reach the throat.
Supporting text
Regarding the consequence if water reaches the throat due to excessive sniffing, Imam Ahmad holds two views: one that the fast is invalidated because the Prophet's prohibition implies invalidation, and another that it does not invalidate the fast because the water reached the throat without intention, similar to flour dust inhaled accidentally.