Sahih Muslim
The Book of Fasting (Kitab Al-Sawm)
Book Number: 006 / Hadith Number: 2426
Ibn 'Umar (Allah be pleased with both of them) said that the Apostle of Allah (may peace be upon him) forbade uninterrupted fasting. They (some of the Companions) said: You yourself fast uninterruptedly, whereupon he said: I am not like you. I am fed and supplied drink (by Allah).