Maintaining the bonds of kinship (silatur-rahim) indeed enjoys extraordinary importance in Islam. Conversely, severing the ties (qata-ur-rahim), is very high on the list of enormities. At two places in the Qur’an, Allah has cursed the one severing family ties.
“And those who break the covenant of Allah, after its ratification, and sever that which Allah has commanded to be joined (i.e. they sever the bond of kinship and are not good to their relatives) and work mischief in the land, on them is the curse, and for them is the unhappy home (i.e. Hell)” [Ar-Rad 13:25. See also Muhammad, 47:22-23].
A cursed person is one who is deprived of the mercy of Allah. It is an indication of this deprivation that this sin is punished in this world as well as in the Hereafter. “There is no sin more deserving of having punishment meted out by Allah to its perpetrator in advance in this world along with what He stores up for him in the next world than oppression and severing ties of family.” [Tirmidhi].
Another hadith highlights the high stakes involved here in a compelling way: “Rahim (family ties) is a word derived from Ar-Rahman (The Compassionate One) And Allah says: ‘I shall keep connection with him who maintains you and sever connection with him who severs you.’” [Bukhari]
Silatur-rahim has been defined as politeness, kind treatment, and concern for all one’s relatives even if distantly related, corrupt, non-Muslim, or unappreciative. [Shaikh Abdul Wakil Durubi in Reliance of the Traveller]. While nearly every religion has emphasized good family relations, Islam has taken it to unprecedented heights. It is a duty to be discharged without an eye for reciprocity. A Muslim is required to be kind even to his non-Muslim relatives. Similarly he is required to be kind to even those relatives who are harsh to him.