Explanation

Kabshah bint Thābit (may Allah be pleased with her) reported that the Messenger of Allah (may Allah's peace and blessings be upon him) once visited her and drank from the mouth of a hanging waterskin while he was in a standing posture. He did that (although he forbade drinking while standing) because this was the only way he could drink from it while it was hanging. So Kabshah got up to the waterskin and cut off its mouth in order to preserve the spot where the Messenger of Allah (may Allah's peace and blessings be upon him) put his mouth to seek blessing from it and to protect it from being handled in a disrespectful manner (given that the Prophet's mouth had touched it).