Assalamu Alaikum Warahamtullahi Wa barakatah I have heard of reports when the prophet would get angry for the sake of Allah, even though he was the most calm of people in any other situation. His face would become red out of anger in certain situations. My question is when is it permissible to show similar anger, or if it is at all? Jazakullahu Khaira
All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His Slave and Messenger.
As you mentioned in the question, the Prophet, sallallaahu ‘alayhi wa sallam, never got angry for his own sake. He, sallallaahu ‘alayhi wa sallam, would get angry only for the sake of Allaah, whenever the commands of Allaah were violated. This is the criterion of anger and it is the answer to your question: "when is it permissible to show similar anger?"
You may express your anger when you see that the sanctities of Allaah are violated. Al-Bukhari entitled a chapter in his Saheeh: "Permissible anger and harshness for the sake of Allaah." He cited a number of Ahaadeeth indicating the anger of the Prophet, sallallaahu ‘alayhi wa sallam, in different situations, and how his anger in all of them was for the sake of Allaah. He, sallallaahu ‘alayhi wa sallam, showed his anger in such situations to emphasize the commands of Allaah, as Al-Haafith Ibn Hajar said in Fat-h Al-Baari.
The Muslim's anger for the sake of Allaah is an indication of his faith; the failure to be angry may incur the discontent of Allaah. Abu Hayyaan reported on the authority of Maalik ibn Dinaar : "Allaah, The Exalted, revealed to the angels to destroy a certain village. The angels said, 'O our Lord, in it is your worshipping slave.' Allaah, The Exalted, said: 'Start with him, for his face never changed (i.e. turned red with anger for the sake of Allaah) when he saw my prohibitions violated).'" [Al-Bahr Al-Muheet]
Abu Hayyaan also said: "A scholar wrote to an ascetic worshipper who withdrew to the desert for the purpose of worship: 'You have abandoned Madeenah to which the Prophet, sallallaahu ‘alayhi wa sallam, migrated and where the divine revelation descended on him, to live in the desert!' He replied, 'How could I not leave a place under your authority when I have never seen your face turned red with anger for the sake of Allaah?' (or he said similar words to the same effect)."
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