Musannaf Ibn Abi Shaybah

Hazrat Abu Alaa says that I was also present at the conquest of Tikrit. We made peace with them on the condition that they would give us a specified amount of wealth and we would grant them safety. So they gave us the wealth. Then one of them was killed by someone, so their monk came to us and said, "Did you not give your Prophet ﷺ, your Commander of the Faithful, and your own pledge, and then you did not uphold that pledge?!" Our leader said, "Present two just witnesses against the killer and we will hand the killer over to you. Or, if you wish, take an oath and we will pay you blood money. And if you wish, we will take an oath, and in that case, you will get nothing." So a meeting was set for the next day. Their priest came and praised Allah Almighty, mentioned the earth and the sky, and spoke of the Day of Judgment. Then he said, "The first reckoning among disputes will be for blood. The two sons of Adam (peace be upon him) will be the parties, and judgment will be passed against one of them. Then, one by one, the reckoning for blood will continue until the matter reaches between us and your companion. Then the slain will say to the killer, 'Why did you kill me?' We do not like that your companion silences our companion by saying, 'Those who came after you received your blood money.'"