In the name of Allah, the Compassionate and Merciful
From Muhammad, who is the servant of Allah and His Prophet to Heracles Caesar.
Peace be on him, who follows the right path.
After this, I invite you to the fold of Islam. Therefore, if you desire security, accept Islam. If you accept Islam, Allah shall reward you doubly and if you refuse to do so, the responsibility for the transgression of the entire nation, shall be yours.
O people of the Book! Leaving aside all matters of differences and disputes, agree on a thing, which is equally incontrovertible both as you and we are concerned and it is that we should not worship any one else with Him, nor regard any one else except Allah as our Sustainer.
If you deny this, you must know that we believe in Oneness of Allah, in all circumstances.
Seal: Allah's Prophet Muhammad
Note: Just as in our time, there are two most powerful States which call themselves 'Super' powers; in the time of the Holy Prophet (S.A.W.) there were two most powerful States: One was Iran and the other Rome or Byzantium or Constantinople. The former was the biggest state of Asia and a cradle of a great civilisation. It was towards the east of Arabia. Towards the north west was the Roman Empire. The two States were contiguous. Rome is at present the Capital of Italy. The Arabs called Byzantium by the name of Rome.
Some years back when this letter was sent, the Iranians attacked Syria and defeated the Romans. There is a reference to it in the Quran. The Romans, in order to avenge themselves, made big preparations and defeated the Iranians. Although the Iranians were at that time very powerful and the Romans did seem to have a chance of a victory against them, the Quran prophesied a clear triumph for the Romans. Heracles came to Jerusalem in token of his gratefulness, It was here that he received the letter of the Holy Prophet(S.A.W.). He ordered that somebody from Arabia, should be presented before him. Per chance Abu Sufyan was staying at Ghaza with his merchandise. The men of Caesar brought him from Ghaza.
Caesar held a grand court. He donned a Crown and sat on his throne. Then addressing the Arabs, he enquired as to who was the relative of the person who claimed himself to be a Prophet. Abu Sufyan said that he was related to the Holy Prophet (S.A.W.). The following dialogue then took place:
Caesar: To what sort of family does the Claimant to Prophethood belong?
Abu Sufyan: Is noble.
Caesar: Did some one else in the family claim Prophethood?
Abu Sufyan: No.
Caesar: Did someone from the family happen to be a King?
Abu Sufyan: No.
Caesar:Are the people who have accepted this religion, poor or influential?
Abu Sufyan: They are poor people.
Caesar: Are his followers growing in number or decreasing?
Abu Sufyan: They are growing.
Caesar: Have you ever experienced an untruthfulness from him?
Abu Sufyan: No.
Caesar: Does he ever break a promise or agreement?
Abu Sufyan: Thus far he has never done it. But it is to be seen if he adheres to the new peace pact which has been oncluded.
Caesar:Have you ever fought a battle against him?
Abu Sufyan: Yes.
Caesar: What was the result of the battle?
Abu Sufyan: Sometime we were victorious and sometime he was successful.
Caesar: What does he teach?
Abu Sufyan: He says
"Worship One God -- Allah. Associate none else with Allah. Say prayers. Take to piety. Speak the truth. Treat relatives with kindness.
After this dialogue Caesar remarked that the Prophets always belonged to noble families. Further he said that as nobody else from the family of the Holy Prophet (S.A.W.) laid claim to Prophethood, it was, therefore, clear that there was no hereditary influence involved in his claim to Prophethood. Similarly absence of any king in the family, proved that the Holy Prophet was not prompted by a desire of kingship. As He never spoke a lie, he could hardly be expected to lie about Allah. Caesar further observed that the followers of the Prophets, in the beginning, are poor and that a true religion goes on making progress. Also Prophets never cheat anybody. As he preached piety, cleanliness and worship of Allah alone, he should one day be a master of the place, he (Caesar) was occupying. Thereafter Caesar ordered that the letter of Holy Prophet (S.A.W.) be read.
The dialogue of Caesar, with Abu Sufyan, highly enraged the courtiers. The Caesar, therefore, sent away the Arabs from the court. The love of crown and throne and the opposition of the courtiers, however, did not allow Caesar to accept Islam. But his searching questions and his talk clearly show that he was convinced of the truthfulness of Islam, as he had correctly judged that a person who never in his life, uttered even a trifling lie, could hardly say anything wrong about Allah. He was also certain that worldly riches, splendour and ascendancy were not the aims and objects of the Holy Prophet (S.A.W.), but the communication of he message of Islam to the entire world, was his mission.
When Caesar was about to return to Constantinople, he again advised his courtiers to follow the Holy Prophet (S.A.W.) as he was the one, they were awaiting. He further mentioned that their books contained the description of the Holy Prophet, Muhammad (S.A.W.), and these clearly and unequivocally indicate that he was the true Prophet of Allah. It was, therefore, in their own interest to follow the guidance given by the Holy Prophet (S.A.W.).
The courtiers, however, said that it would mean their acceptance of the over lordship of the Arabs, although their's was the biggest kingdom of the world and their nation the greatest nation of the world. Caesar, thereon, said that although they were not prepared to accept Islam then very shortly they would be overpowered by the Arabs. He was much displeased by the arrogant attitude of the courtiers and immediately left Syria. While departing he looked at the Syrian territory and said that he was leaving Syria for ever. And it was true, he was never to return to Syria.'