It is narrated from Sayyiduna Abdullah bin Abbas (may Allah be pleased with them both) that when the Haruriyyah (the Khawarij) came out, they gathered in a house, and they were six thousand. I came to Sayyiduna Ali (may Allah be pleased with him) and said: "O Commander of the Believers, delay the prayer until it is cooler, so that I may go to these people and speak with them." He said: "I fear for you." I said: "Not at all." (Abu Zumayl said:) Ibn Abbas (may Allah be pleased with them both) was handsome and had a loud voice. Ibn Abbas said: I went to them wearing the finest of Yemeni garments. I greeted them with salam, and they said: "Welcome to you, O Ibn Abbas! What is this garment?" I said: "What fault do you find with me? I have seen the finest garments on the Messenger of Allah (peace and blessings be upon him)." And I recited the verse: "Say: Who has forbidden the adornment of Allah which He has brought forth for His servants, and the good things of provision?" [Surah al-A'raf: 32] Then he mentioned his famous debate with them. This hadith is sahih (authentic) on the condition of Muslim, but the two Shaykhs (Bukhari and Muslim) did not record it.