The Prophet ﷺ said, "Expel water from your nose thoroughly two or three times."
حدثنا يحيى عن ابن أبي ذئب حدثني قارظ عن أبي غطفان قال رأيت
قال النبي ﷺ استنثروا مرتين بالغتين أو ثلاثا
Its isnad is sahih. Qariz is Ibn Shayba bin Qariz, the ally of Banu Zahra, and he is trustworthy. Nasai said, "There is no harm in him," and Ibn Hibban mentioned him among the trustworthy narrators, and Bukhari gave his biography in al-Kabir 4/1/201 without mentioning any criticism of him. Abu Ghatfan is Ibn Tarif al-Murri, a trustworthy successor, deemed trustworthy by Ibn Main, Nasai, and others.The hadith was narrated by Abu Dawud and Ibn Majah, as noted in al-Muntaqa 241, and the Hafiz mentioned in al-Tahdhib 7:307 that Nasai also narrated it. Bukhari narrated it in al-Kabir, in the biography of Qariz, from Adam from Ibn Abu Dhib, and it will come up again at 2889. However, in the printed edition it appears as "abshiru" instead of "istabshiru," which is an error.