If a son performs Hajj on behalf of his deceased father who had committed many sins, will all the father's sins be forgiven, and will he receive the same reward he would have obtained had he performed Hajj during his lifetime?

If a son performs Hajj on behalf of his deceased father, the father receives the reward given to one who performs Hajj himself, including the expiation of sins, provided that the son performed it free from transgression and obscenity. It is recommended to perform Hajj on behalf of deceased or incapacitated parents. If the father died before performing Hajj, despite fulfilling the conditions of obligation, it becomes obligatory for his children to pay for someone to perform Hajj on his behalf. If one of them volunteers to do so, it is commendable and carries immense virtue. It is a prerequisite to perform Hajj for oneself first before performing Hajj on behalf of the father.