What is the ruling on the end-of-service bonus and retirement pension for a father who worked in a usurious bank, knowing that the retirement pension will be disbursed from the Social Insurance Fund?

It is permissible for an employee at a Riba-based bank to take an end-of-service bonus for the period he worked before knowing of its prohibition. However, it is not permissible for him to take it for the period he worked after knowing of its prohibition. It is lawful for his children to take from their father's prohibited wealth because their maintenance is obligatory upon him, provided they advise him and do not overindulge in taking.