Abu Imran al-Jawni relates: I said to Sayyiduna Jundub bin Abdullah (may Allah be pleased with him): "I have given my pledge to Ibn al-Zubayr (may Allah be pleased with them both) that I will fight the people of Syria." He said: "Perhaps you want to say: 'Jundub gave me a fatwa and I am following him'?" I said: "That is not my intention; rather, I am asking you for a fatwa so that you may give me one." So he said: "Ransom yourself with your wealth." I said: "They will not accept that from me." Jundub (may Allah be pleased with him) said: "In the time of the Messenger of Allah (peace and blessings be upon him) I was a young boy, and such-and-such a person told me that the Messenger of Allah (peace and blessings be upon him) said: 'On the Day of Resurrection the slain man will bring his killer with him, clinging to him, and Allah, the Mighty and Majestic, will say: "For what reason did you kill him?" He will say: "For the sake of so-and-so's kingship."' So fear lest you become that man."
Hadith Referenceالمعجم الكبير للطبراني / باب الجيم / 1664