What is the ruling of the Shari'ah regarding a father's refusal to provide for his children and his ex-wife after their divorce, knowing that he is financially well-off and the children believe his refusal is due to magic? And how can living expenses be managed in this situation?

If the mother's divorce is revocable, she is entitled to maintenance during the waiting period (iddah). If it is irrevocable, she is not entitled to maintenance unless she is pregnant. The maintenance of children is obligatory upon the father if they are not yet adult and have no wealth. As for adults, if they are wealthy, they are not entitled to maintenance. If they are poor, maintenance is obligatory for the female until her marriage, and for the male if he is unable to earn a living due to illness or similar reasons. It is preferable for a well-off father to spend on his adult children during their educational stages. If the father's negligence is due to magic, he should be guided to perform legal ruqyah, and the children must honor their father in all circumstances.