The Prophet ﷺ went to relieve himself and instructed me to bring him three stones. I found two stones but could not find a third, so I picked up a piece of dung and brought them all to the Prophet ﷺ. He took the two stones and threw away the dung, saying, "This is filth."
حدثنا يحيى بن آدم حدثنا زهير حدثنا أبو إسحاق قال ليس أبو عبيدة ذكره ولكن عبد الرحمن بن الأسود عن أبيه أنه
أتى النبي ﷺ الغائط وأمرني أن آتيه بثلاثة أحجار فوجدت حجرين ولم أجد الثالث فأخذت روثة فأتيت بهن النبي ﷺ فأخذ الحجرين وألقى الروثة وقال هذه ركس
Its isnad is sahih. Its meaning has already appeared with an interrupted isnad at 3685, where we noted that the narration of Zuhayr from Abu Ishaq, which is this narration, was narrated by Bukhari. It will also come again at 4056, and see 4299.