Hadith on Takfir: Cursing, excommunicating a Muslim like killing him

‘Imran ibn Husayn reported: The Messenger of Allah, peace and blessings be upon him, said, “If a man declares his brother to be an unbeliever, it is as if he has killed him. Cursing a believer is like killing him.

Source: Musnad al-Bazzār 3158

Grade: Sahih (authentic) according to Al-Albani

عَنْ عِمْرَانَ بْنِ حُصَيْنٍ رَضِيَ اللَّهُ عَنْهُ قَالَ قَالَ رَسُولُ اللَّهِ صَلَّى اللهُ عَلَيْهِ وَسَلَّمَ إِذَا قَالَ الرَّجُلُ لِأَخِيهِ يَا كَافِرُ فَهُوَ كَقَتْلِهِ وَلَعْنُ الْمُؤْمِنِ كَقَتْلِهِ

3158 مسند البزار

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