ANSWER:

You should intervene if you have the ability to stop the fight but not to take part in it, especially if your friend is the aggressor. 

If a person approaches my close friend and starts hitting him for whatever reason, can I fight back to protect my Muslim brother. Or is the physical hitting between them two and I get involved I will be sinful?

Etiquette, Morals and Heart-Softeners | October 20, 2019 1:53 am
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If someone did extreme wrong to other person and this person does not want to forgive him at all.Whats the rulling of islam for the person who did wrong to other;he has to repent to Allah only or he has to ask forgiveness from the person also to whome he wronged.What if he only repent to Allah and do not ask forgiveness from human and this human always cursed him because of his wrong doing.
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