Mu'jam Kabir Tabarani 7240 — We were a people of traders, and the war

Abu Sufyan bin Harb (may Allah be pleased with him) said: We were a people of traders, and the war between us and the Messenger of Allah (peace and blessings be upon him) had hemmed us in until our wealth was ruined. When the truce came between us and the Messenger of Allah (peace and blessings be upon him), we did not feel secure about our wealth. So I set out with a group of Quraysh towards Syria, where our trade was. I arrived there at the time when Heraclius had prevailed over the Persians who had opposed him and had driven them back from it, and he had recovered his great cross, which they had seized from him. When this news reached him, and it reached him that his cross had been recovered for him — and Hims was his residence — he set out from it on foot, giving thanks to Allah for restoring to him what He had restored, in order to pray in Bayt al-Maqdis. Carpets were spread for him along the road, and flowers were strewn on them. When he reached Iliya' and performed his prayer there, with his patricians and the bishops of Rome with him, he said: The letter of the Messenger of Allah (peace and blessings be upon him) reached him with Dihyah bin Khalifah al-Kalbi (may Allah be pleased with him): "In the name of Allah, the Most Gracious, the Most Merciful. From Muhammad, the Messenger of Allah, to Heraclius, the great one of the Romans. Peace be upon whoever follows guidance. To proceed: accept Islam and you will be safe; accept Islam and Allah will give you your reward twice over. But if you turn away, the sin of the peasants will be upon you." Muhammad bin Ishaq (may Allah have mercy on him) said: Ibn Shihab (may Allah have mercy on him) said: The bishop of the Christians told me — he said: I met him in the time of Abd al-Malik bin Marwan, and he claimed that he had witnessed this concerning the affair of the Messenger of Allah (peace and blessings be upon him), the affair of Heraclius, and his intelligence — he said: When the letter of the Messenger of Allah (peace and blessings be upon him) reached him with Dihyah (may Allah be pleased with him), he took it and placed it between his thighs and his waist. He said: Then he wrote to a man in Rome who read Hebrew, telling him of his affair and informing him of what he had brought. He said: The man in Rome wrote to him that this is the prophet we have been waiting for, there is no doubt about it, so follow him and believe in him. So Heraclius gave orders concerning the patricians of Rome, and they were gathered for him in his royal palace, and at his command its doors were shut upon them. Then he looked down on them from an upper storey, fearing for himself from them, and said: O people of Rome! I have gathered you for some news. The letter of this man has come to me, inviting me to his religion, and by Allah! He is the man we have been waiting for and whom we find in our scripture. So come, let us follow him and believe in him, so that both our world and our Hereafter may be secure. They snorted like one man, then rushed to the doors of the palace to get out of it, and found them locked against them. He said: Bring them back to me — fearing for himself from them. So they were brought back to him, and he said: O people of Rome! I only said what I said to you to see how firm you are in your religion in the face of this new matter that has arisen, and I have seen from you what pleases me. So they fell down in prostration to him, and he ordered the doors of the palace to be opened for them, and they went away.