Is beating one's wife permissible in Islam, and what is its ruling, method, justifications, and regulations, if it is permissible?

The Sharia’s concern with preserving the marital bond has surrounded it with a protective framework of rulings that establish its foundations. The rulings of Sharia are built upon bringing about benefits and warding off harms. Hitting a wife without justification is oppression and aggression, based on the Almighty’s saying: “And do not hold onto them with intent to harm them and commit aggression,” and the Prophet’s (peace be upon him) saying: “There should be no harm nor reciprocating harm.” As for the legitimate Sharia justification for hitting, it is the wife’s defiance (nushuz), after admonition and abandonment in bed, provided that the hitting is not severe, does not leave a mark or blemish, is done with a non-harmful instrument such as a miswak (tooth-cleaning twig), does not strike the face, and is not accompanied by insults. The intention behind it must be reform, not revenge, and it should cease once the objective is achieved. Hitting is permissible, not recommended, and forgiveness is better. If the hitting is for discipline and reform and does not achieve its purpose, then it is not prescribed, and it may not be prescribed if it leads to a greater harm. Spouses should observe compassion and avoid resorting to this situation.