Sayyiduna Abu Hurayrah (may Allah be pleased with him) says: This is the story of the Islam of Thumamah bin Uthal al-Hanafi. When Thumamah confronted the Messenger of Allah (peace and blessings be upon him), the Messenger of Allah (peace and blessings be upon him) prayed to Allah that Allah would give him power over him; he had confronted him while still a polytheist and had intended to kill him. Then Thumamah, still in a state of polytheism, was passing through Madinah with the intention of performing Umrah when the Companions seized him and presented him in the court of the Messenger of Allah (peace and blessings be upon him). By his order he was tied to one of the pillars of the mosque. The Messenger of Allah (peace and blessings be upon him) came to him and asked: "O Thumamah! How are you? Has Allah given (us) power over you?" He said: "O Muhammad! If you kill me, you will kill a man whose blood will be avenged. If you (peace and blessings be upon him) forgive, the forgiveness will be met with gratitude. If you (peace and blessings be upon him) want wealth, wealth will also be given." The Messenger of Allah (peace and blessings be upon him) left him in that state and went away. The next day he came again and asked: "How are you, Thumamah?" He said: "I am well, O Muhammad! If you kill me, you will kill a man whose blood will be avenged. If you forgive, the forgiveness will be met with gratitude. If you ask for wealth, it will be given." The Messenger of Allah (peace and blessings be upon him) went away again. Sayyiduna Abu Hurayrah (may Allah be pleased with him) says: We poor ones sat talking about Thumamah's blood, (saying:) By Allah! Rather than Thumamah's blood, fat, healthy camels as ransom in exchange for him would be better. Then in the morning the Messenger of Allah (peace and blessings be upon him) came to him and asked: "Thumamah, how are you?" He said: "I am well, O Muhammad! If you kill, you will kill a man whose blood will be avenged. If you forgive, the forgiveness will be met with gratitude. If you ask for wealth, wealth will also be given." The Messenger of Allah (peace and blessings be upon him) said: "Release Thumamah. O Thumamah! I have forgiven you." Then Thumamah took a bath in one of the gardens of Madinah, purified his clothes and his body, and came back while the Messenger of Allah (peace and blessings be upon him) was sitting among his Companions. He said: "O Muhammad (peace and blessings be upon him)! No face was more hateful to me than your face, no religion was more hateful to me than your religion, and no city seemed more hateful to me than your city." Then he said: "Now no face is more beloved (to me) than your face, no religion seems better than your religion, and no city seems better than your city. I bear witness that there is no god but Allah and that Muhammad (peace and blessings be upon him) is the servant and Messenger of Allah. O Messenger of Allah! I set out for Umrah while still on the religion of my people; give me glad tidings concerning my Umrah. May Allah send mercy upon you." He gave him glad tidings and also taught him the method. He set out for Umrah. When he came to Makkah and the Quraysh heard him speak about his religion, they began to say: Thumamah has abandoned his religion. They angered Thumamah. Thumamah said: "I have not abandoned religion; I have accepted Islam, affirmed the truth of Muhammad (peace and blessings be upon him) and believed in him. By Allah! Not a single grain of wheat will come to you from Yamamah (and Yamamah was a fertile place) as long as I live, unless the Prophet (peace and blessings be upon him) gives permission." He went back to his land, and on arriving he stopped the grain to Makkah until the Quraysh fell into hardship. They wrote to the Messenger of Allah (peace and blessings be upon him), invoking their ties of kinship, asking him to write to Thumamah to send the grain, so the Messenger of Allah (peace and blessings be upon him) issued an order to Thumamah to send the grain.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب السير / 18031