What is the ruling on offering supererogatory prayers during the Friday and Eid sermons? Is it forbidden or merely disliked? And what is the ruling on offering prayers at the time of the Adhan (call to prayer)?

For someone who enters the mosque while the Imam is delivering the Friday sermon, it is recommended for him to perform the Tahiyyat al-Masjid (mosque greeting prayer).

Regarding supererogatory prayers (nafl) at the time of Eid prayer: Shafi'is: There is no harm in performing supererogatory prayers before and after the Eid prayer for anyone other than the Imam. Hanbalis: Supererogatory prayers are disliked before and after the Eid prayer at the prayer ground. Hanafis: The soundest opinion is that supererogatory prayers are disliked before it, whether at the prayer ground or elsewhere. Malikis: Supererogatory prayers are disliked at the prayer ground before and after the Eid prayer, unlike in the mosque where they are permissible.

If a person enters while the Imam is delivering the Eid sermon: Shafi'is: If it is in a mosque, it is preferable for him to pray the Eid prayer, as it suffices for the Tahiyyat al-Masjid, and it is permissible to begin with the Tahiyyah. Malikis and Hanafis: He should sit without praying.

It is better for someone who hears the adhan (other than the second adhan for Friday) and wishes to perform supererogatory prayers to wait until the mu'adhdhin finishes, so he can repeat after the adhan and make supplication afterward. However, it is not forbidden for him to pray supererogatory prayers during the adhan.