Mishkat al-Masabih #344

Salman said that a polytheist jestingly remarked, “I see that your friend teaches you even about your excrement,” to which he replied, “Yes, he has commanded us not to face the qibla, or cleanse ourselves with our right hands, or be satisfied with less than three stones among which there is no dung or bone.” Muslim and Ahmad transmitted it, the wording being Ahmad’s.