Answer: As for reciting it after the obligatory prayers, I know of no evidence for that from the Sunnah of the Messenger of Allah, peace and blessings be upon him. What has been reported is the recitation of Ayat al-Kursi, “Qul Huwa Allahu Ahad,” “Qul A‘udhu bi-Rabbi-l-Falaq,” and “Qul A‘udhu bi-Rabbi-n-Nas.” The ḥadiths mention the recitation of these sūrahs after the five daily prayers, whereas I am unaware of any proof for the legitimacy of reciting al-Fātiḥah after the prayer.
The sūrahs just mentioned are not to be read collectively in a raised voice; rather, each Muslim should recite them individually and quietly, between himself and his Lord.
As for reciting al-Fātiḥah for the souls of the deceased, this is an innovation. No one should recite al-Fātiḥah—or any portion of the Qur’an—for the souls of the dead, because nothing of that is found in the Sunnah of the Messenger of Allah, peace and blessings be upon him, nor in the practice of the early generations of this Ummah. It is a newly-introduced matter, whether done in the mosque, the graveyard, the home, or elsewhere. What is authentically known regarding the dead—if they were Muslims—is to pray for their forgiveness and mercy, to give charity on their behalf, and to perform Hajj for them; these are the actions supported by the evidence.
Reciting the Qur’an for the souls of the dead, or reciting al-Fātiḥah for them, is therefore a newly-invented practice and a blameworthy innovation.
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Raising the voice in supplication and remembrance after the prayer and at other times
Question: What is your view on raising the voice in supplication and remembrance in general, and after the prayer in particular? Should supplication and remembrance be done aloud, silently, or somewhere in between?