On various occasions, Imam al-Sajjad (as) made it clear that Yazid ibn Mu‘awiyah was Imam al-Husayn's (as) killer.
1. When they brought Imam al-Sajjad (as) to Yazid ibn Mu‘awiyah, the son of Mu‘awiyah addressed Imam al-Sajjad (as) in this way, "Are you the son of that man who has been killed by Allah?" Imam al-Sajjad (as) replied, "I am ‘Ali, the son of the man whom you have killed." Then, Imam al-Sajjad (as) recited this verse,
﴿ وَمَن يقتُل مُؤمِناً مُتَعَمِّداً فَجَزآؤُهُ جَهَنَّمُ خالِداً فيها ... ﴾
"And whoever kills a believer intentionally, his punishment is hell; he shall abide in it forever.40"41
2. At another time, Imam al-Sajjad (as) said, "O Yazid! It is enough of your shedding our blood..."42
3. Ibn A‘tham relates, "Imam al-Sajjad (as) addressed Yazid as follows, ‘If only you could perceive what you have done against my father, if only you could comprehend what you have done against my Household, and if only you could understand what you have done against the rights of my brothers and uncles, then you would run away to the hills and mountains. There, you would spread gravel stones and roll yourself upon them. You would raise your voice high weeping for yourself. How is it possible that the head of al-Husayn (as), the son of Fatimah (as) and ‘Ali (as), has been hung on the city gates when he was Allah's trust among you, the people?'"43
4. There is also Imam al-Sajjad's (as) address to Yazid in his famous sermon in Damascus, when he said, "Is the Muhammad that you talk about your ancestor or my ancestor? If you want to pretend that he is your ancestor, you have undoubtedly lied and become a disbeliever. And if you say that he is my ancestor, then why have you killed his progeny?"44
Notes:
40. Surat al-Nisa' 4:93.
41. Tadhkirah al-Khawass, p. 63, as narrated by Ghazali.
42. Maqatil al-Talibiyyin, p. 120.
43. Ibn A‘tham, Al-Futuh, vol. 3, section [bab] 5, p. 132.
44. Ibid., p. 133; Khwarazmi, Maqtal al-Imam al-Husayn (as), vol. 2, p. 242.
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