In the Islamic lunar calendar, Muslims are familiar with a well-known sunnah practice known as Ayyam al-Bidh fasting. This voluntary fast is observed for three days each month. Specifically, it were to be observed on the 13th, 14th, and 15th of the Hijri month. These days are referred to as the “white days” because their nights are illuminated by the moon at its brightest.
In addition to being a devotional practice exemplified by the Prophet Muhammad (peace be upon him), this fast carries great virtue for Muslims who seek consistency in their voluntary acts of worship.
However, a recurring question often arises, particularly during the month of Dhu al-Hijjah. Is it still permissible to observe Ayyam al-Bidh fasting on the 13th of Dhu al-Hijjah, given that it falls within the Days of Tashriq?
This question must be answered by referring to authentic Islamic sources. In Islam, enthusiasm for worship must always remain in harmony with the guidance of the Prophet (peace be upon him).
The Days of Tashriq are the 11th, 12th, and 13th of Dhu al-Hijjah. In several hadiths, the Prophet explained that these are days designated for eating, drinking, and increasing remembrance of Allah. Therefore, fasting on these days is prohibited, except for pilgrims performing Hajj who are unable to offer the required sacrificial animal (hady).
As narrated from a hadith recorded by Muhammad al-Bukhari:
عَنْ عَائِشَةَ وَابْنِ عُمَرَ رَضِيَ اللَّهُ عَنْهُمْ قَالَا: لَمْ يُرَخَّصْ فِي أَيَّامِ التَّشْرِيقِ أَنْ يُصَمْنَ إِلَّا لِمَنْ لَمْ يَجِدِ الْهَدْيَ
“From ‘Aisyah bint Abi Bakr and Abdullah ibn Umar (may Allah be pleased with them): ‘No concession was granted to fast during the Days of Tashriq except for those who could not find a sacrificial animal.’” (Sunan al-Bukhari)
This hadith indicates that the general ruling regarding fasting during the Days of Tashriq is prohibition. The only exception applies to certain Hajj pilgrims who are unable to perform the sacrifice.
This prohibition is reinforced in another narration recorded by Muslim ibn al-Hajjaj:
عَنْ نُبَيْشَةَ الْهُذَلِيِّ قَالَ: قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ: أَيَّامُ التَّشْرِيقِ أَيَّامُ أَكْلٍ وَشُرْبٍ وَذِكْرٍ لِلَّهِ
“From Nubaisyah al-Hudzali (may Allah be pleased with him), Rasulullah (peace be upon him) said: ‘The days of Tashriq are days of eating, drinking, and remembering Allah.’”
This narration highlights the special nature of these days in Islamic law. Muslims are encouraged to enjoy Allah’s blessings while increasing remembrance and gratitude. Maintaining closeness to Allah could be done more than just by abstaining from food and drink through fasting.
Another narration reported by Ahmad ibn Hanbal further clarifies this ruling:
عَنْ عَبْدِ اللَّهِ بْنِ حُذَافَةَ أَنَّ النَّبِيَّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ أَمَرَهُ أَنْ يُنَادِيَ فِي أَيَّامِ التَّشْرِيقِ: إِنَّهَا أَيَّامُ أَكْلٍ وَشُرْبٍ
“From Abdullah bin Hudzafah (may Allah be pleased with them), The Prophet instructed that it be proclaimed during the Days of Tashriq: ‘These are days of eating and drinking.’”
Thus, it is clear that the Days of Tashriq should not be used for observing the Ayyam al-Bidh fast.
Nevertheless, the recommendation to fast three days each month remains valid, including during Dhu al-Hijjah.
Therefore, a person may still observe voluntary fasting on the 14th and 15th of Dhu al-Hijjah. The third day, moreover, could be replaced with another date later in the month, such as the 16th. This approach preserves the spirit of the sunnah without violating the Prophet’s prohibition.
This flexibility is also supported by a narration from Aisha bint Abi Bakr, recorded by Muslim ibn al-Hajjaj and Al-Tirmidhi:
عَنْ مُعَاذَةَ الْعَدَوِيَّةِ قَالَتْ: قُلْتُ لِعَائِشَةَ: أَكَانَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ يَصُومُ مِنْ كُلِّ شَهْرٍ ثَلَاثَةَ أَيَّامٍ؟ قَالَتْ: نَعَمْ فَقُلْتُ: مِنْ أَيِّ أَيَّامِ الشَّهْرِ كَانَ يَصُومُ؟ قَالَتْ: لَمْ يَكُنْ يُبَالِي مِنْ أَيِّ أَيَّامِ الشَّهْرِ يَصُومُ
“Mu‘adzah al-‘Adawiyah said: I asked Aisha bint Abi Bakr, ‘Did the Messenger of Allah (peace be upon him) fast three days of every month?’ Aisha replied, ‘Yes.’ I then asked, ‘On which days of the month did he usually fast?’ She answered, ‘He did not mind which days of the month he fasted.’” (Sunan Muslim and Tirmidhi)
This hadith demonstrates that Ayyam al-Bidh does not have to occur strictly on the 13th, 14th, and 15th. While those dates are preferred, they are not obligatory. As long as the fast is observed for three days within the month and does not conflict with Islamic prohibitions, the sunnah is still fulfilled.
Thus, Ayyam al-Bidh fasting in Dhu al-Hijjah remains permissible. However, the 13th must be omitted because it falls within the Days of Tashriq. In its place, one may fast another day outside the prohibited period.
