What are the regulations concerning a wife's obedience to her husband in sexual intimacy, and what are the circumstances in which she is permitted to refuse without sin? Does this contradict the obligation of her obedience to him so long as he does not command her to commit a sin?

A wife's obedience to her husband is one of the greatest duties, especially regarding intimacy. However, this obedience is restricted by the absence of harm and by being within her capacity, as Allah Almighty says: "Allah does not burden a soul beyond its capacity," and "He has not placed upon you in religion any difficulty." Therefore, obedience is not obligatory if the husband requests something forbidden or something that physically or psychologically harms her, and according to the Hadith: "Indeed, obedience is only in what is good and right," and "There should be no harm nor reciprocating harm." The intimacy for which obedience is obligatory is that which is customary and proper. What falls outside the bounds of natural disposition and common custom does not necessitate obedience.