What is the ruling of Islamic law concerning a marriage that has taken place, where the husband only discovered after the marriage that his wife is afflicted with an illness of which he was unaware, and he is now hesitant to separate from her due to her inability to raise his children, and he is in constant dispute with her mother and suspects that she has bewitched him, and he beats his wife and verbally abuses her with vile language?

Retinal atrophy is not a defect that necessitates the husband's option to annul the marriage. However, some scholars believe that any defect that causes the other spouse to recoil from it and prevents the fulfillment of the marriage's purpose necessitates this option. But your brother knew about the defect and continued the marital relationship, which indicates consent and forfeits his right to annulment. Divorce is a right for the man if he sees that his marital life is not sustainable. It is advised to be patient and try to solve the problems, to distance oneself from the wife's mother if she is the cause of the problems, to review the way of dealing with the wife if her bad character is the cause of the problems, and to seek help from experts. Allah (SWT) says: (But if you dislike them – perhaps you dislike a thing and Allah makes therein much good). If the problems cannot be resolved, there is no sin in divorce, and the dowry will be her right.