Sahih Muslim
The Book of Drinks (Kitab Al-Ashriba)
Book Number: 023 / Hadith Number: 5018
Anas reported that Allah's Apostle (may peace be upon him) forbade that a person should drink while standing. Qatada reported: We said to him: What about eating? Thereupon he (Anas) said: That is even worse and more detestable (abominable).