Firstly:

The Day of ῾Arafah is one of the greatest days and carries immense reward. The Prophet (peace be upon him) said, as narrated by Jābir (may Allāh be pleased with him): “There is no day better in the sight of Allāh than the Day of ῾Arafah. Allāh descends to the lowest heaven and boasts to the inhabitants of the heavens about the people on earth.” In another narration: “Indeed, Allāh boasts about the people of ῾Arafah to His angels and says: ‘Look at My servants, they have come to Me disheveled and dusty.'” [Narrated by Abū Ya῾lā, Ibn Khuzaymah, and Ibn Ḥibbān].

Also, regarding the reward of this day, ῾Aā᾽ishah (may Allāh be pleased with her) reported that the Messenger of Allāh (peace be upon him) said: “There is no day on which Allāh frees more people from the Fire than the Day of ῾Arafah. He draws near, then boasts about them to the angels, saying, ‘What do these people want?'” [Narrated by Muslim].

Secondly:

It is recommended for Muslims to take advantage of these special days, as the Prophet (peace be upon him) said, as narrated by Muḥammad ibn Maslamah from Al-Ṭabarānī: “Indeed, your Lord has breaths of mercy in the days of your lives, so expose yourselves to them. Perhaps you may be touched by one of them, and you will never be miserable thereafter.”

Allāh says: “They hasten to good deeds, and they outstrip others therein” [Al-Mu᾽minūn 23:61].

Since the Day of ῾Arafah carries such specific rewards, it is distinguished by particular acts of worship and good deeds, including:

1. Takbīr (Glorification of Allāh):
   • Takbīr is a Sunnah for ῾Iīd al-᾽Aḍḥā, and it is of two types:
     • Unrestricted Takbīr: This is not bound to any specific time and can be recited during the night or day, starting from the beginning of Dhul-Ḥijjah until the end of the days of Tashrīq.
     • Restricted Takbīr: This is recited after the obligatory prayers. The scholars have various opinions on its beginning and ending times:
       • Ḥanafī school:
         • There are three opinions:
           • The first: According to Imam Abū Ḥanīfah (may Allāh have mercy on him), the Takbīrs begin at Fajr on the Day of ῾Arafah and end after ῾Aṣr on the Day of ῾Iīd.
           • The second: According to Abū Yūsuf (may Allāh have mercy on him), Takbīr begins after Ẓuhr on the Day of ῾Iīd and ends after ῾Aṣr on the third day of Tashrīq.
           • The third, which is the widely accepted position in the Ḥanafī school: Takbīr begins after the Fajr prayer on the Day of ῾Arafah and ends after the ῾Aṣr prayer on the last day of Tashrīq, which is the fourth day of ῾Iīd.
       • Mālikī school: Takbīr starts after Ẓuhr on the Day of ῾Iīd and ends after the Fajr prayer on the fourth day (the last day of Tashrīq), totaling fifteen prayers.
       • Shāfi῾ī school: The time for Takbīr begins at Fajr on the Day of ῾Arafah and ends at sunset on the third day of Tashrīq.
       • Ḥanbalī school: Takbīr starts after the Fajr prayer on the Day of ῾Arafah if the person is not in ᾽Iḥrām, and after Ẓuhr on the Day of Sacrifice (῾Iīd al-᾽Aḍḥā) if they are in ᾽Iḥrām, and it ends after ῾Aṣr on the last day of Tashrīq.

Therefore, the majority of scholars say that the restricted Takbīr after the prayers begins at Fajr on the Day of ῾Arafah, which is the opinion of the Ḥanafīs (in their relied-upon position), Shāfi῾īs, and Ḥanbalīs. The Mālikīs differ, saying it begins after Duhr on the Day of ῾Iīd. Regarding its ending time, the Ḥanafīs (in their relied-upon position) and Ḥanbalīs say it ends after ῾Aṣr on the fourth day (the third day of Tashrīq), while the Shāfi῾īs say it ends at sunset on the fourth day, and the Mālikīs say it ends after Fajr on the fourth day.

2. Fasting:
   • Fasting on the Day of ῾Arafah is recommended and carries immense reward. The Prophet (peace be upon him) said, as narrated by Abū Qatādah: “Fasting on the Day of ῾Arafah, I hope from Allāh, will expiate for the sins of the previous year and the coming year.” [Narrated by Muslim].
3. Supplication (Du῾ā᾽):
   • Supplication on the Day of ῾Arafah is highly encouraged and is more likely to be answered. The Prophet (peace be upon him) said: “The best supplication is the supplication on the Day of ῾Arafah, and the best thing I and the Prophets before me have said is: ‘lā ᾽ilāha ᾽illā Allāh waḥdahu lā sharīka lah lah-u al-mulk wa-lah-u al-ḥamd wa-huwa ῾alā kulli sha᾽in qadīr‘ (There is no god but Allāh, alone, without partner. His is the dominion, and His is the praise, and He has power over all things).” [Narrated by Al-Tirmidhī].
4. Sending blessings and peace upon the Prophet (peace be upon him):
   • Sending blessings upon the Prophet (peace be upon him) is a key to divine blessings and acceptance. Among the best-known invocations for this purpose is what Imam Muḥammad ibn Sulaymān al-Jazūlī mentioned in his book “Dalā᾽il al-Khayrāt,” which is known for its hidden and manifest blessings.
5. Charity:
   • Giving charity on this day is recommended to bring joy to the hearts of Muslims and to share in the joy of ῾Iīd, particularly by helping those in need.

Regarding the second part of the question:

The permissibility of gathering in the mosque for supplication and remembrance, especially after ῾Aṣr on the Day of ῾Arafah, is an act that is fundamentally lawful and encouraged by general texts promoting collective remembrance and supplication. This is supported by the well-known ḥadīth: “Whenever a group of people gather in one of the houses of Allāh, reciting the Book of Allāh and studying it among themselves, tranquility descends upon them, mercy envelops them, the angels surround them, and Allāh mentions them to those near Him.” [Narrated by Muslim].

Additionally, this practice was observed by some of the Companions, including Ibn ῾Abbās and ῾Amr ibn Ḥurayth, and was known as “Ta῾rīf.” Ibn Qudāmah stated: “There is nothing wrong with ‘Ta῾rīf‘ (gathering for supplication) on the eve of ῾Arafah in other cities. Al-᾽Athram reported that he asked Imam ῾Aḥmad about people gathering in the mosques on the Day of ῾Arafah for supplication. He said, ‘I hope there is nothing wrong with it, as it was done by several people.’ Al-᾽Athram narrated from al-Ḥasan: ‘The first person to gather people in Basra on the Day of ῾Arafah was Ibn ῾Abbās.’ Imam ᾽Aḥmad said: ‘The first to do it was Ibn ῾Abbās and ῾Amr ibn Ḥurayth.’ Al-Ḥasan, Bakr, Thābit, and Muḥammad ibn Wāsi῾ would attend the mosque on the Day of ῾Arafah. Imam ῾Aḥmad said: ‘There is nothing wrong with it; it is merely supplication and remembrance of Allāh.’ When asked if he would do it himself, he said, ‘As for me, no.’ It is also reported that Yaḥyā ibn Ma῾īn attended the gathering on the eve of ῾Arafah.” [Al-Mughnī].

Al-Ḥasan al-Baṣrī said: “The first to initiate ‘Ta῾rīf‘ in Basra was Ibn ῾Abbās (may Allāh be pleased with him). He would go to the mosque, supplicate, and sit for the remembrance of Allāh on the Day of ῾Arafah.”

In Sunan al-Bayhaqī, Abū ῾Awānah said: “I saw Al-Ḥasan al-Baṣrī on the Day of ῾Arafah after ῾Aṣr sitting and supplicating, remembering Allāh, and people entering the mosque and gathering.”

Therefore, gathering for supplication is permissible and even recommended to encourage people to participate.

Someone might ask: Is it better to engage in remembrance individually or in a group?

The preference for individual or collective remembrance depends on the situation of each person. For someone who finds that individual remembrance enhances their devotion and minimizes distractions, individual remembrance is better. For someone who feels more motivated in a group setting, or who may struggle with formulating supplications on their own, collective remembrance is preferable.

Each has a precedent at the time of the Salaf, as we have explained.

Fatwā issued by Dr. Khālid Naṣr