question #1 Sahih Muslim 279d, Book 2, Hadith 117 : What is the prescribed method for purifying a utensil that has been licked by a dog in Islamic teachings?

The Messenger of Allah (ﷺ) said: The purification of the utensil belonging to any one of you, after it is licked by a dog, lies in washing it seven times, using sand for the first time.