Musnad Ahmad Hadith 21064

A man from Abdul Qais who was with the Khawarij and then separated from them says that the Khawarij entered a town, and from there, Abdullah bin Khabbab (may Allah be pleased with him) came out in fear, dragging his sheet. The Khawarij said to him, "Do not be afraid." He replied, "By Allah, you have frightened me." The Khawarij asked, "Are you Abdullah, the son of Khabbab (may Allah be pleased with him), the companion of the Prophet (ﷺ)?" He replied, "Yes." The Khawarij said, "Have you heard any hadith from your father regarding the Prophet (ﷺ) that you can narrate to us?" He replied, "Yes, I heard my father say regarding the Prophet (ﷺ) that the Prophet (ﷺ), mentioning the time of tribulations, said: 'In that time, the one who is sitting will be better than the one who is standing, and the one who is standing will be better than the one who is walking, and the one who is walking will be better than the one who is running. If you reach that time, then become the slain servant of Allah, not the killer servant of Allah.'" The Khawarij asked, "Did you really hear this from your father regarding the Prophet (ﷺ)?" He replied, "Yes." So they seized Abdullah, took him to the bank of the river, and martyred him there. His blood was flowing as if it were a sandal strap that had not been separated. Then they ripped open the belly of his slave woman (umm walad) and killed her child as well.