Assalaamu alaykum. I read in your fatwas that it is a religious innovation to arrange a feast 40 days after the death of someone. What if one customarily gathers his relatives after his father's death (with no emphasis on a specific day and date) and arranges a feast for them where some poor people are also invited? This is not done as a specific act of worship.
All perfect praise be to Allah, the Lord of the worlds. I testify that there is none worthy of worship except Allah and that Muhammad is His slave and Messenger.
What you pointed out to is correct. We have highlighted in many fatwas that what some people do of gathering people and holding banquets after forty days of someone's death and so on has no basis in the Shariah and is considered a religious innovation that contradicts the Sunnah of the Prophet and the guidance of the Companions and the Salaf (righteous predecessors).
As regards gathering one’s relatives after the death of his father in a customary manner without specifying a day or date and inviting some poor and needy people along with them and holding a banquet for them, then we do not see any objection to this. Moreover, if this takes place as a charity on behalf of the deceased or just for feeding the people, which is Islamically recommended, then this is a good deed.
The scholars agreed that charity on behalf of the deceased person [i.e. while intending the reward for the dead] is accepted. They provided evidence for this with many ahaadeeth, among which is the hadeeth narrated by ‘Aa’ishah, may Allah be pleased with her, who said, "A man said to the Prophet 'My mother has died suddenly. I think that if she were able to talk, she would have given charity. So if I give charity now on her behalf, will she get the reward?' The Prophet said, 'Yes.'" [Al-Bukhaari and Muslim]
It is also confirmed that the Prophet said, "O people, spread the greeting of peace (i.e. say: Assalaamu alaykum to one another), feed the people, and perform the prayer when others are asleep, and you will enter Paradise in peace." [At-Tirmithi and others - Al-Albaani classified it as saheeh (sound)]
Allah knows best.
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