Abu Ghalib said: I was walking with Sayyiduna Abu Umamah (may Allah be pleased with him) while he was riding his donkey, until we reached the steps of Damascus, and there were some heads set up there. He asked: What are these heads? It was said: These are the heads of the Kharijites, brought from Iraq. At that he said: "The dogs of the Fire, the dogs of the Fire" - three times - "the worst of the slain beneath the sky" - he said it three times - "the best of the slain is the one whom they killed" - he said it three times - "glad tidings to the one who killed them and to the one whom they killed" - he said it three times. Then he wept, and I said: O Abu Umamah, why are you weeping? He said: "Out of pity for them; they were among the people of Islam, then they went out of Islam." Then he recited: "It is He who has sent down to you the Book; in it are verses that are precise - they are the foundation of the Book" [Al Imran: 7] until he finished the verses. Then he recited: "And do not be like those who became divided and differed after the clear proofs had come to them" [Al Imran: 105] until he reached: "they will be in the mercy of Allah, abiding therein forever" [Al Imran: 107]. I said: O Abu Umamah, are these the ones? He said: "Yes." I said: Is this something you are saying from your own opinion, or something you heard from the Messenger of Allah (peace and blessings be upon him)? He said: "I would never be so bold" - three times - "I heard it from the Messenger of Allah (peace and blessings be upon him) not once or twice, but seven times." Then he put his finger in his ears and said: "Otherwise, may these two be made deaf."
Hadith Referenceالمعجم الكبير للطبراني / باب الصاد / 8003