Sunan An-Nasa'i

It was narrated from Musa bin Talhah that:a man brought a rabbit to the Prophet, and the prophet stretched out his hand toward it, then the one who had brought it said: ""I saw some blood on it,"" So the Prophet drew his hand back, but he told the people to eat. Among the people there was a man who held back. The Prophet said: ""What is the matter with you?"" He said: ""I am fasting."" The Prophet said to him: ""Why don't you fast on the three days of Al-Bid, the thirteenth, fourteenth and fifteenth?