عن أبى سعيد الخدرى رضى الله عنه أن النبي صلى الله عليه وسلم نهى عن النفخ في الشراب، فقال رجل : القذاة أراها في الإناء؟ فقالب: "أهرقها" قال: إني لا أروى من نفس واحد؟ قال: "فأبن القدح إذاً عن فيك".((رواه الترمذي))
Narrated Abu Sa'id Al-Khudri (May Allah be pleased with him) reported:
The Messenger of Allah (ﷺ) prohibited us blowing in the drinking water. A man said: "O Messenger of Allah! Sometimes I see some litter floating about on the surface. What should I do then?" He (ﷺ) replied, "Pour them out." Then the man said: "My thirst is not quenched with one draught." Messenger of Allah (ﷺ) said, "Then put away the cup from your mouth (in between three gulps), and take breath."
وعن أم ثابت كبشة بنت ثابت أخت حسان بن ثابت رضى الله عنه وعنها قالت: دخل عليَّ رسول الله صلى الله عليه وسلم، فشرب من فيّ قربة معلقة قائماً، فقمت إلى فيها فقطعته ((رواه الترمذي وقال: حديث حسن صحيح)).
وإنما قطعتها لتحفظ موضع فم رَسُول اللَّهِ ﷺ وتتبرك به وتصونه عن الابتذال. وهذا الحديث محمول على بيان الجواز، والحديثان السابقان لبيان الأفضل والأكمل، والله أعلم.
Narrated Umm Thabit Kabshah (May Allah be pleased with her), daughter of Thabit (May Allah be pleased with him) and the sister of Hassan bin Thabit, the Prophet's poet) reported:
The Messenger of Allah (ﷺ) visited me and drank some water from a hanging water-skin while he was in a standing posture. So, I stood up and cut off the mouth (of that water-skin)..
An-Nawawi said that the reason why she did this was to preserve the part of the water-skin which the lips of Messenger of Allah (ﷺ) touched, gain blessings from it, and preserve it from dishonor. This narration is understood to show permissibility whereas the previous two narrations are to show what is better and closer to perfection. Allah knows best.