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."'

أَخْبَرَنَا مُحَمَّدُ بْنُ مَنْصُورٍ، قَالَ حَدَّثَنَا سُفْيَانُ، عَنْ حَكِيمِ بْنِ جُبَيْرٍ، وَعَمْرِو بْنِ عُثْمَانَ، وَمُحَمَّدِ بْنِ عَبْدِ الرَّحْمَنِ، عَنْ مُوسَى بْنِ طَلْحَةَ، عَنِ ابْنِ الْحَوْتَكِيَّةِ، قَالَ قَالَ عُمَرُ رضى الله عنه مَنْ حَاضِرُنَا يَوْمَ الْقَاحَةِ قَالَ قَالَ أَبُو ذَرٍّ أَنَا أُتِيَ رَسُولُ اللَّهِ ﷺ بِأَرْنَبٍ فَقَالَ الرَّجُلُ الَّذِي جَاءَ بِهَا إِنِّي رَأَيْتُهَا تَدْمَى . فَكَانَ النَّبِيُّ ﷺ لَمْ يَأْكُلْ ثُمَّ إِنَّهُ قَالَ " كُلُوا " . فَقَالَ رَجُلٌ إِنِّي صَائِمٌ . قَالَ " وَمَا صَوْمُكَ " . قَالَ مِنْ كُلِّ شَهْرٍ ثَلاَثَةُ أَيَّامٍ . قَالَ " فَأَيْنَ أَنْتَ عَنِ الْبِيضِ الْغُرِّ ثَلاَثَ عَشْرَةَ وَأَرْبَعَ عَشْرَةَ وَخَمْسَ عَشْرَةَ " .