Narrated Anas:
The Prophet fasted Al-Wisal on the last days of the month. Some people did the same, and when the news reached the Prophet he said, “If the month had been prolonged for me, then I would have fasted Wisal for such a long time that the most exaggerating ones among you would have given up their exaggeration. I am not like you; my Lord always makes me eat and drink.”
Sahih Bukhari, Volume 9, Book90, Number 347