What are the duties of a daughter for her parents after her marriage? What are the duties of husband for his wife's parents?
All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.
The obligations of a daughter towards her parents are the same as they were before her marriage. She has to be kind with them, treat them with kindness, obey them in what is permissible and spend on them if they are poor while she is wealthy and able to give to them.
It is her parents who raised her while she was small and they felt pity for her while she was weak till she became a grown lady and men became interested in marrying her. The marriage then is but one of the many favors of her parents. Therefore, the marriage should confirm their rights rather than abrogating them or decreasing them.
Everyone who considers the texts of the Quran and the Sunnah will find that they stress the rights of parents. No doubt, marriage adds to the obligation of a woman the rights of her husband, children, and taking care of the house, etc. Thus, in order to deal with them correctly she needs to be wise and strong enough to give everyone his right without making any imbalance among the rights.
As for the duties of a husband towards his parents in-law, in general, they are as the duties of a Muslim towards any other Muslim, in addition to the rights of the relationship established by marriage. Allah made a strong means for kindred by marriage. Allah Says (what means): {And it is He who has created from water a human being and made him [a relative by] lineage and marriage. And ever is your Lord competent [concerning creation].} [Quran 25: 54]
The characteristics of noble men are to be kind with their in-laws as the Prophet was a perfect person in this matter as well as other matters.
To conclude, each spouse is obliged to treat each other kindly, and being good with one's in-laws is actually a sign of being good with one's spouse.
Allah knows best.
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