It was narrated that Ibn Al- Hawtakiyyah said:
Umar, May Allah be pleased with us on the day when we stopped at Al-Qaha?' Abu Dharr said: 'I was. A rabbit was brought to the Messenger Allah and the man who brought it said: I saw it bleeding (menstruating). The Prophet did not eat, then he said: Eat. A man said: I am fasting. He said: What fast are you observing? He said: Three days each month He said: Why don't yo0u fast the bright shining days, the thirteenth, fourteenth and fifteenth. '