Salamunalaikum,
What are the authentic accounts to support chest-beating from Qur'an and Hadith? Note: My question is not specific to shia or sunni books. I just need authentic hadith whether from shia accounts or sunni. I also don't need a logical answer so a hadith or quranic verse is needed which verifies the act of chest-beating.
Also, If matam/chest-beating is allowed, then, to what extent? Is it allowed to mourn every person like we mourn Imam Husayn (عليه السلام)? For instance, if someone's family member dies and he is neither a martyr nor an oppressed but simply died due to sickness or normal reasons. Then, are we allowed to beat our chest and face and cry loudly while mourning him?
I need a detailed answer for this. If the question is not clear then please let me know.
Note: This question is not concerned with qama or zanjeer and forms of matam/chest beating in which blood is spilled.
Wassalam