What is the religious ruling regarding the case of a father who left his job in the army based on his son's promise to send him half of his salary, and then the son broke his promise, then renewed it by swearing on the Holy Quran, and then broke it again, relying on a fatwa that he is not obligated to support his father who is not in need, and that fulfilling a promise is not legally binding? Does the father have a mandatory right over the son in this case, and is fulfilling a covenant binding, and what is the extent of the authenticity of the hadith "You and your wealth belong to your father"?

The son is obligated to pay half of his salary to his father, due to the father abandoning his work in reliance on his son's promise. This is based on the general verses and hadiths that call for fulfilling promises, and because the Hanafis and Malikis deem this type of promise binding. Ibn Nujaym stated that a promise is binding if it is conditional, and the Malikis obligate the promisor legally if the promisee incurs a difficulty, or if the promise was linked to a stated reason. This is also a view among the Hanbalis, and was chosen by Sheikh al-Islam Ibn Taymiyyah.

Furthermore, the resolution of the Islamic Fiqh Academy states that a promise is religiously binding unless there is an excuse, and legally binding if it is contingent on a reason and the promisee incurred a cost as a result of the promise. The effect of the obligation is determined either by fulfilling the promise or by compensating for the damage. In addition, the son's failure to abide by his promise to his father is considered an act of disobedience (ʿuqūq).

The father is advised to be gentle with his son and not to burden him in a way that causes him to fall short in the essential rights of his wife and children, especially if the father is wealthy or has another son who supports him financially.