ANSWER:

This is not permissible, you must not fast Sunnah fasts on behalf of the deceased as this is an innovation and it won’t reach him.

My brother passed away this past July. I know we can make dua and fast on behalf of the deceased. My question is I’ve fasted on the day of Ashoora on his behalf. Will he get the reward of sin being wiped away from previous year? Of course sins being forgiven for the following year wouldn’t count because he is no longer in this world.

Fasting, Funerals | September 22, 2019 3:42 am
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Is it authentic that in the state which a person dies will be resurrected in the same state on the day of judgement? For example if he dies while doing a haraam activity will he be resurrected while doing the same activity?
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if people do innovations like quran khatm and tasbeeh for the deceased etc. Will the deceased be punished for it in the grave?