From his father, that the Messenger of Allah ﷺ said: "When one of you drinks, then do not breathe into the vessel." (Using translation from Tirmidhī 1889)  

أَنَّ رَسُولَ اللهِ ﷺ قَالَ «إِذَا شَرِبَ أَحَدُكُمْ فَلَا يَتَنَفَّسْ فِي الْإِنَاءِ»