Explanation of the hadith
The Prophet (may Allah's peace and blessings be upon him) forbade turning the waterskins upside down and then drinking from their mouths, because they may contain harmful things that could enter one's stomach and harm him.
The Messenger of Allah (may Allah's peace and blessings be upon him) forbade turning the waterskins upside down and drinking from their mouths
Authentic hadithNarrated by Bukhari & MuslimHadeethEnc #5452
عن أبي سعيدٍ الخُدْرِيِّ رضي الله عنه قال: نهى رسولُ اللهِ صلى الله عليه وسلم عن اخْتِنَاثِ الأَسْقِيَةِ.
English translation
Abu Sa‘īd al-Khudri (may Allah be pleased with him) reported: The Messenger of Allah (may Allah's peace and blessings be upon him) forbade turning the waterskins upside down and drinking from their mouths.
Manners of Eating and Drinking