What did Heraclius come to know about Prophet Muhammad (peace be upon him) after asking questions to Abu Sufyan?
      Narrated 'Abdullah bin 'Abbas:                          Abu Sufyan bin Harb informed me that Heraclius had sent a messenger to     him while he had been accompanying a caravan from Quraish. They were      merchants doing business in Sham (Syria, Palestine, Lebanon and      Jordan), at the time when Allah's Apostle had truce with Abu Sufyan      and Quraish infidels. So Abu Sufyan and his companions went to      Heraclius at Ilya (Jerusalem). Heraclius called them in the court and      he had all the senior Roman dignitaries around him. He called for his      translator who, translating Heraclius's question said to them, "Who      amongst you is closely related to that man who claims to be a      Prophet?" Abu Sufyan replied, "I am the nearest relative to him      (amongst the group)."     Heraclius said, "Bring him (Abu Sufyan) close to me and make his      companions stand behind him." Abu Sufyan added, Heraclius told his      translator to tell my companions that he wanted to put some questions      to me regarding that man (The Prophet) and that if I told a lie they      (my companions) should contradict me." Abu Sufyan added, "By Allah!      Had I not been afraid of my companions labeling me a liar, I would not     have spoken the truth about the Prophet. The first question he asked      me about him was:     'What is his family status amongst you?'      I replied, 'He belongs to a good (noble) family amongst us.'      Heraclius further asked, 'Has anybody amongst you ever claimed the      same (i.e. to be a Prophet) before him?'     I replied, 'No.'     He said, 'Was anybody amongst his ancestors a king?'     I replied, 'No.'     Heraclius asked, 'Do the nobles or the poor follow him?'     I replied, 'It is the poor who follow him.'     He said, 'Are his followers increasing decreasing (day by day)?'     I replied, 'They are increasing.'     He then asked, 'Does anybody amongst those who embrace his religion      become displeased and renounce the religion afterwards?'     I replied, 'No.'     Heraclius said, 'Have you ever accused him of telling lies before his      claim (to be a Prophet)?'     I replied, 'No. '     Heraclius said, 'Does he break his promises?'     I replied, 'No. We are at truce with him but we do not know what he      will do in it.' I could not find opportunity to say anything against      him except that.     Heraclius asked, 'Have you ever had a war with him?'     I replied, 'Yes.'     Then he said, 'What was the outcome of the battles?'     I replied, 'Sometimes he was victorious and sometimes we.'     Heraclius said, 'What does he order you to do?'     I said, 'He tells us to worship Allah and Allah alone and not to      worship anything along with Him, and to renounce all that our      ancestors had said. He orders us to pray, to speak the truth, to be      chaste and to keep good relations with our Kith and kin.'     Heraclius asked the translator to convey to me the following, I asked      you about his family and your reply was that he belonged to a very      noble family. In fact all the Apostles come from noble families      amongst their respective peoples. I questioned you whether anybody      else amongst you claimed such a thing, your reply was in the negative.     If the answer had been in the affirmative, I would have thought that      this man was following the previous man's statement. Then I asked you      whether anyone of his ancestors was a king. Your reply was in the      negative, and if it had been in the affirmative, I would have thought      that this man wanted to take back his ancestral kingdom.     I further asked whether he was ever accused of telling lies before he      said what he said, and your reply was in the negative. So I wondered      how a person who does not tell a lie about others could ever tell a      lie about Allah. I, then asked you whether the rich people followed      him or the poor. You replied that it was the poor who followed him.      And in fact all the Apostle have been followed by this very class of      people. Then I asked you whether his followers were increasing or      decreasing. You replied that they were increasing, and in fact this is     the way of true faith, till it is complete in all respects. I further      asked you whether there was anybody, who, after embracing his      religion, became displeased and discarded his religion. Your reply was     in the negative, and in fact this is (the sign of) true faith, when      its delight enters the hearts and mixes with them completely. I asked      you whether he had ever betrayed. You replied in the negative and      likewise the Apostles never betray. Then I asked you what he ordered      you to do. You replied that he ordered you to worship Allah and Allah      alone and not to worship any thing along with Him and forbade you to      worship idols and ordered you to pray, to speak the truth and to be      chaste. If what you have said is true, he will very soon occupy this      place underneath my feet and I knew it (from the scriptures) that he      was going to appear but I did not know that he would be from you, and      if I could reach him definitely, I would go immediately to meet him      and if I were with him, I would certainly wash his feet.' Heraclius      then asked for the letter addressed by Allah's Apostle     which was delivered by Dihya to the Governor of Busra, who forwarded      it to Heraclius to read. The contents of the letter were as follows:      "In the name of Allah the Beneficent, the Merciful (This letter is)      from Muhammad the slave of Allah and His Apostle to Heraclius the      ruler of Byzantine. Peace be upon him, who follows the right path.      Furthermore I invite you to Islam, and if you become a Muslim you will     be safe, and Allah will double your reward, and if you reject this      invitation of Islam you will be committing a sin by misguiding your      Arisiyin (peasants). (And I recite to you Allah's Statement:)     'O people of the scripture! Come to a word common to you and us that      we worship none but Allah and that we associate nothing in worship      with Him, and that none of us shall take others as Lords beside Allah.     Then, if they turn away, say: Bear witness that we are Muslims (those      who have surrendered to Allah).' (3:64).     Abu Sufyan then added, "When Heraclius had finished his speech and had     read the letter, there was a great hue and cry in the Royal Court. So      we were turned out of the court. I told my companions that the      question of Ibn-Abi-Kabsha) (the Prophet Muhammad) has become so      prominent that even the King of Bani Al-Asfar (Byzantine) is afraid of     him. Then I started to become sure that he (the Prophet) would be the      conqueror in the near future till I embraced Islam (i.e. Allah guided      me to it)."     The sub narrator adds, "Ibn An-Natur was the Governor of llya'      (Jerusalem) and Heraclius was the head of the Christians of Sham. Ibn      An-Natur narrates that once while Heraclius was visiting ilya'      (Jerusalem), he got up in the morning with a sad mood. Some of his      priests asked him why he was in that mood? Heraclius was a foreteller      and an astrologer. He replied, 'At night when I looked at the stars, I     saw that the leader of those who practice circumcision had appeared      (become the conqueror). Who are they who practice circumcision?' The      people replied, 'Except the Jews nobody practices circumcision, so you     should not be afraid of them (Jews).     'Just Issue orders to kill every Jew present in the country.'     While they were discussing it, a messenger sent by the king of Ghassan     to convey the news of Allah's Apostle to Heraclius was brought in.      Having heard the news, he (Heraclius) ordered the people to go and see     whether the messenger of Ghassan was circumcised. The people, after      seeing him, told Heraclius that he was circumcised. Heraclius then      asked him about the Arabs. The messenger replied, 'Arabs also practice     circumcision.'     (After hearing that) Heraclius remarked that sovereignty of the 'Arabs     had appeared. Heraclius then wrote a letter to his friend in Rome who      was as good as Heraclius in knowledge. Heraclius then left for Homs.      (a town in Syrian and stayed there till he received the reply of his      letter from his friend who agreed with him in his opinion about the      emergence of the Prophet and the fact that he was a Prophet. On that      Heraclius invited all the heads of the Byzantines to assemble in his      palace at Homs. When they assembled, he ordered that all the doors of      his palace be closed. Then he came out and said, 'O Byzantines! If      success is your desire and if you seek right guidance and want your      empire to remain then give a pledge of allegiance to this Prophet      (i.e. embrace Islam).'     (On hearing the views of Heraclius) the people ran towards the gates      of the palace like onagers but found the doors closed. Heraclius      realized their hatred towards Islam and when he lost the hope of their     embracing Islam, he ordered that they should be brought back in      audience.     (When they returned) he said, 'What already said was just to test the      strength of your conviction and I have seen it.' The people prostrated     before him and became pleased with him, and this was the end of      Heraclius's story (in connection with his faith).