Is it religiously permissible to dispose of money received from a teaching job, knowing that this money was withheld for three years then disbursed after the events of the revolution?

If the work system does not allow combining two jobs or receiving two salaries, and an additional salary was disbursed by mistake, or due to corruption, or due to the worker's dereliction of duty; it is not permissible for him to benefit from this money.

He must return it to the employer if possible, and if he is fairly certain that it will be returned to the state treasury. Otherwise, he must dispose of it by spending it on general Muslim welfare (such as hospitals, schools, and mosques); due to the Almighty's saying: (O you who have believed, do not betray Allah and the Messenger or betray your trusts while you know [the consequence].) Al-Anfal/27, and due to the Prophet's (peace be upon him) saying: (Indeed, men delve into the wealth of Allah without right, and for them is the Fire on the Day of Resurrection.) Narrated by Al-Bukhari.

It is stated in the fatwas of the Permanent Committee that an employee's salary is not permissible for him unless his employment was legitimate and he performed the required work; otherwise, what he took is not permissible for him, and he must return it or give it as charity along with repentance. Moreover, it is obligatory for the employee to perform his work as required, and if he fails to do so without a valid Sharia excuse, the salary is not permissible for him, and he must repent and give as charity what he took without excuse.