Is it obligatory to seek the father's permission for working to earn money for marriage, knowing that he will most likely not agree, and what should I do in this case?

We advise you to seek your father’s permission regarding your desire for marriage and work, and to be gentle with him, explaining your need and desire, and that you are consulting him and seeking his help. If he refuses, seek assistance from some relatives to persuade him. If that does not help, and you are in need of marriage, then there is no objection to working to obtain what you need for marriage, and you will not be considered disobedient; because it is not permissible for a father to prevent his adult, rational, and mature son from lawful earning. Nevertheless, the son must placate his father and deal with him patiently, persistently requesting his permission to work. If the father does not grant it, and the son is in need of earning, then he is not obligated to obey his father by abandoning it. However, if the father is in dire need of the son remaining at home due to illness or disability, then the son must stay; because that is part of the obligatory act of filial piety.