Hadith: that the Prophet (may Allah's peace and blessings be upon him) prohibited blowing in one's drink

عن أبي سعيد الخدري رضي الله عنه أن النبي صلى الله عليه وسلم نهى عنِ النَّفْخ في الشّراب، فقال رجل: القَذَاة أَرَاهَا في الإناء؟ فقال: «أَهْرِقْهَا». قال: إِنِّي لا أَرْوى من نَفَس واحد؟ قال: «فَأَبِنِ القدح إذًا عن فِيك».
[صحيح] - [رواه الترمذي وأحمد ومالك والدارمي]

Abu Sa‘īd al-Khudri (may Allah be pleased with him) reported that the Prophet (may Allah's peace and blessings be upon him) prohibited blowing in one's drink. A man said: “Sometimes, I see a speck in the vessel. What should I do then?” He replied: “Spill it.” Then the man said: “My thirst is not quenched with one draught.” He said: “Then remove the cup from your mouth (in between three gulps, and take a breath).”
[Authentic hadith] - [Narrated by At-Termedhy - Narrated by Ahmad - Maalik - Ad-Daarimi]

Explanation

The Prophet (may Allah's peace and blessings be upon him) prohibited blowing in one's drink. A man asked him: “O Messenger of Allah, there might be a speck in it, so one blows in it to remove it.” The Prophet (may Allah's peace and blessings be upon him) said: “Spill the water that has the speck in it, and do not blow in it.” Then the man asked him: “My thirst is not quenched with one breath.” So the Prophet (may Allah's peace and blessings be upon him) ordered him to remove the cup from his mouth, take a breath, and then drink again.