The wife is equal to her husband within a marital relationship. The Holy Quran called each "one half of a pair", as each, bears responsibility for the worries and feelings of the other half and thus they both form a complete pair.
However, this equality in principle, does not contradict the fact that there are duties and responsibilities unique and specific to each part of this relationship, such us the responsibility of the man to protect and maintain his wife and family, which is termed "qawama". The responsibility of the woman within her marital home obliges her to play an educational and advisory role towards her husband, as she extends advice to him and wishes him the best at all times. She must call him to do good whenever he falls short of doing so, and must prohibit him for indulging into wrong-doing, as this is the obligation upon each and every Muslim towards the other, such as a son towards his father, a student towards his or her teacher, and a citizen towards his or her ruler. However, this commanding good and prohibiting evil must be within the regulations and boundaries mentioned by the scholars in sound books and references. Thus, the marital relationship does not by any means, annul the act of enjoining good and forbidding evil, but rather emphasizes and stresses it.
As for the question: Does the husband enjoy any authority over his wife, and to what extent? The answer would be: the husband enjoys the 'qawama" explained above, but it is not by any means, an absolute and infinite authority. Rather it is an authority which is restricted by the regulations of the Sharia and the considerations of the society within which one lives.
In principle, the affairs of the marital home and the family must be done in consultation between the husband and wife, as consultation can only bring good. However, if they fail to reach an agreement, then the husband shall have the authority to decide. It is not for the husband to force his wife to do anything, merely to fulfill his desires under the pretense of 'obedience of the husband.'
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