Praise be to Allaah.
There are jaahili customs, or reprehensible innovations, and you have to give them up and explain to others that they are wrong.
With regard to reciting Qur’aan over the grave of the deceased, this is not permissible, and none of the Salaf did this. If it were good to do this, they would have done it before us. It has been reported that Soorat Yaa-Seen should be recited for the person who is dying, before his soul departs, but after he has died and when he is being buried and after the burial, there is nothing that should be recited, and one should not tell him to say “Laa ilaaha ill-Allaah” and so on.
Offering condolences is Sunnah, but it need not be during the mourning ceremonies. Condolences may be offered to the family of the deceased in all places. There is nothing wrong with all the relatives of the deceased gathering together in one place so that people may come and offer their condolences, but they should not gather for the purpose of eating. Food should be prepared only for the immediate family of the deceased; it is makrooh for them to offer food to others.
There is no need to gather this money from everyone, unless the family are poor, in which case they may be given zakaat funds.
It is not permissible to slaughter this sheep, whether it is from the wealth of the deceased or from someone else. But if food is prepared for the family of the deceased, from one or more animals, there is nothing wrong with this.
Collecting these pebbles, and making dhikr whilst doing so, and putting them on the grave – this is a reprehensible innovation (bid’ah) which must be given up and denounced.
Raising one’s voice in wailing and lamenting, striking the cheeks and eulogizing the deceased are all bid’ah and actions of the jaahiliyyah. It was reported in a hadeeth: “He is not one of us who strikes his cheeks, rends his garments and calls with the call of the jaahiliyyah.”
(Narrated by al-Bukhaari, 1294, Fath 3/163; Muslim, 103; Ahmad, 1/244).
Wearing black as a sign of mourning for the deceased is bid’ah; but the wives of the deceased should avoid wearing fancy or adorned clothes, jewellery, makeup and perfume during their period of mourning.
It is bid’ah for women to avoid their usual work and activities; the newly-widowed woman can still prepare food, clean the house, wash the dishes, do laundry, etc. There is nothing wrong with her doing that.
And Allaah knows best.