The Messenger of Allah ﷺ said, "Be thorough in sniffing water into the nose, unless you are fasting."
حدثنا قتيبة بن سعيد حدثني يحيى بن سليم عن إسمعيل بن كثير عن عاصم بن لقيط بن صبرة
قال رسول الله ﷺ بالغ في الاستنشاق إلا أن تكون صائما
No references are available.
[Its isnad is sahih] mentioned previously, no. 142. Tirmidhi also narrated it in the Book of Fasting, chapter on the dislike of exaggerating in sniffing water up the nose while fasting, no. 788, as did Ibn Majah, no. 407, from the hadith of Yahya bin Salim, through the same route, and Nasai narrated it, no. 87.