“None of you truly believes (in Allah and in His religion) until he loves for his brother what he loves for himself”
It says “he loves for his brother” – not “she loves for her sister”.
Still, this hadith is one of the most commonly used to force and manipulate women to accept polygyny. If you don’t accept polygyny, you disapprove of something that allah has made permissible. If you don’t embrace the fact that your husband wants a second wife you are selfish and low in deen. If you don’t want your husband do be happy and intimate with another woman, you transgress against your husband and the ummah. If you don’t welcome your co-wife and treat her like a sister and share your husband with her gladly, you disobey the command: love for your sister what you love for yourself.
But it doesn’t say women must “love for your sister that which you love for yourself”.
It says men must “love for your brother that which you love for yourself”.
All of you out there who claim that the quran and the hadiths are to be taken literally, all of you who read the “two or three or four” and say this must be so – why don’t you read this literally:
“love for your brother that which you love for yourself”
Brother – not sister. Look at your wife and ask yourself: Do you love for your brother that which you love for yourself? Because if you don’t, you have no right to ever ask it of your wife!
“Verily, the hypocrites will be in the lowest depth of the Fire; no helper will you find for them[al-Nisaa’ 4:145]