Muhammad bin Ja'far bin al-Zubayr narrates: Umayr bin Wahb al-Jumahi and Safwan bin Umayyah were sitting in the Hatim, shortly after the loss Quraysh suffered at Badr. Umayr bin Wahb was one of the devils of Quraysh; he was among those who used to harm the Messenger of Allah (peace and blessings be upon him) and his Companions, and when they were in Makkah those noble ones faced great hardship from this man. Umayr's son, Wahb bin Umayr, was among the prisoners of Badr. The narrator says: They mentioned the polytheists who had died at Badr, and then (Safwan) said: By Allah! There is no good in life after them. Umayr bin Wahb said: You speak the truth. By Allah! Were it not for a debt upon me which I have no means of paying, and were I not anxious about the expenses of my family, I would ride to (Sayyiduna) Muhammad (peace and blessings be upon him) and kill him. I also have a pretext concerning those people, namely that my son is a prisoner with them. The narrator says: Safwan bin Umayyah seized upon this matter as an opportunity and said: Paying your debt is my responsibility; I will pay it on your behalf. And your family will stay with my family; I will treat them equally as long as they remain, and we will show no inability towards them. Umayr said: Then you must keep my affair and yours secret. He said: Very well. Then Umayr gave orders concerning his sword; its edge was sharpened and it was dipped in poison. Then he set out for Madinah. Sayyiduna Umar (may Allah be pleased with him) was in Madinah among some Muslims; they were talking about the Battle of Badr, how Allah Almighty had honoured them and how their enemy had faced defeat. Meanwhile Sayyiduna Umar (may Allah be pleased with him) saw Umayr bin Wahb tying his mount at the door of the mosque, with a sword hanging from his neck. He said: This dog, by Allah, Umayr bin Wahb! He has surely come with nothing but evil intent. This is the very man who tried to stir up trouble among us and who counted our numbers for the enemy on the day of the Battle of Badr. Then Sayyiduna Umar (may Allah be pleased with him) came to the Prophet (peace and blessings be upon him) and said: O Messenger of Allah! Here is Umayr bin Wahb; he has come with a sword hanging on him. The Prophet (peace and blessings be upon him) said: "Bring him in!" Sayyiduna Umar (may Allah be pleased with him) went, took hold of the sword at Umayr's neck, and brought him in seizing him by the neck. Sayyiduna Umar (may Allah be pleased with him) said to some men of the Ansar who were with him: Go to the Prophet (peace and blessings be upon him) and sit with the Prophet (peace and blessings be upon him), and guard against this dog attacking him (peace and blessings be upon him), for he is a danger. Then he brought him to the Prophet (peace and blessings be upon him), with Sayyiduna Umar (may Allah be pleased with him) holding the strap of his sword. The Prophet (peace and blessings be upon him) said: "O Umar! Let him go! O Umayr! Come forward!" He came near and said: "An'imu sabahan" (May you have a pleasant morning); this was the particular way of greeting one another in the days of Ignorance (Jahiliyyah). The Prophet (peace and blessings be upon him) said: "Allah Almighty has honoured us with a better way of greeting than your greeting, O Umayr! Saying 'As-salamu alaykum' is the greeting of the people of Paradise." He said: By Allah! O (Sayyiduna) Muhammad (peace and blessings be upon him), I have only ever been familiar with this (greeting). The Prophet (peace and blessings be upon him) said: "What have you come for?" He said: I have come concerning that prisoner who is with you people. The narrator says: I think the narration contains these words: The Prophet (peace and blessings be upon him) said: "What is the reason for this sword on your neck?" He said: May Allah Almighty ruin these swords; have they been of any use to us? The Prophet (peace and blessings be upon him) said: "Tell me the truth: what have you come for?" He said: I have come only for this purpose. The Prophet (peace and blessings be upon him) said: "No! Rather, you and Safwan bin Umayyah were sitting in the 'Hatim', and the two of you were talking about the men of Quraysh who were killed at Badr, and you said: Were it not for a debt upon me and were I not concerned about my children, I would go out and kill (Sayyiduna) Muhammad (peace and blessings be upon him). So Safwan took upon himself your debt and the expenses of your children, on the condition that you kill me; but Allah Almighty stands as a barrier between you and that." Umayr said: I bear witness that you are truly the Messenger of Allah. O Messenger of Allah! Previously we used to deny you regarding the news of the heavens which you brought to us, and we also denied the revelation that was sent down to you. But in this matter, only Safwan and I were present. By Allah! I have come to know that none but Allah Almighty could have told you about it. So all praise belongs to Allah Almighty, who guided me to Islam and brought me to this point. Then he bore the testimony of truth. The Prophet (peace and blessings be upon him) said: "Teach your brother his religion! Teach him to read the Qur'an, and release his prisoner for him!" Then Umayr said: O Messenger of Allah! Previously I used to strive hard to extinguish the light of Allah, and I used to cause severe hardship to those who followed the religion of Allah. Now I wish that you give me permission: I will go to Makkah and invite those people to Allah and to Islam. Perhaps Allah Almighty will guide them; otherwise I will harm them just as I used to harm your (peace and blessings be upon him) Companions on account of their religion. The Prophet (peace and blessings be upon him) gave him permission, and he went to Makkah. When Umayr bin Wahb had set out from Makkah, Safwan had said to Quraysh: Receive glad tidings of news that will soon come to you, and that news will make you forget the loss of Badr. Safwan kept asking riders about Umayr bin Wahb, until a rider came and told Safwan that Umayr had accepted Islam. Safwan then swore an oath that he would never speak to him and would never bring him any benefit. When Umayr came to Makkah, he stayed there and began inviting people to Islam, and he would cause harm to whoever opposed him. Then many people accepted Islam at Umayr's hand.
Imam al-Tabarani recorded it as a "mursal" report, and its chain is jayyid (good).