In a sermon delivered in a Fallujah mosque on July 18, 2015, the first day of Eid Al-Fitr, an unnamed ISIS-affiliated cleric stated that the enmity between Sunnis and Shiites is of an ideological nature, and vowed to slaughter Shiites "like sheep" in Baghdad and in the holy Shiite cities of Karbala and Najaf.
ISIS Cleric: You should know, oh servants of Allah, that our enmity with the Rafidites and the Zoroastrian Persians is not of a material or a political nature. It is an ideological enmity that goes back a long time.
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It is time for the Rafidites to face the truth: Their war against the Sunnis is a lost cause. They had tried their whoremonger-luck in the south of Fallujah...
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We are ready for you, oh enemies of Islam. By Allah, all we have in store for you is slaughter. Allah willing, we shall slaughter you like sheep. We are ready for you, and we have plenty of time. We shall confront you in Baghdad, Allah willing. We shall confront you in defiled Karbala, Allah willing. We shall confront you in disgusting Najaf, Allah willing.
ISIS Cleric: You should know, oh servants of Allah, that our enmity with the Rafidites and the Zoroastrian Persians is not of a material or a political nature. It is an ideological enmity that goes back a long time.
[...]
It is time for the Rafidites to face the truth: Their war against the Sunnis is a lost cause. They had tried their whoremonger-luck in the south of Fallujah...
[...]
We are ready for you, oh enemies of Islam. By Allah, all we have in store for you is slaughter. Allah willing, we shall slaughter you like sheep. We are ready for you, and we have plenty of time. We shall confront you in Baghdad, Allah willing. We shall confront you in defiled Karbala, Allah willing. We shall confront you in disgusting Najaf, Allah willing.