The Prophet (Peace be upon him) also sent letters to Mundhir b. Sawa, ruler of Bahrain; (52) Jayfar b. al-Julanda, and 'Abd b. al-Julanda (53) Azdi, rulers of 'Oman; Haudha b. 'Ali, the ruler of al-Yamama (54) and Harith b. Shammar al-Ghassan. Mundhir b. Sawa and the two sons of al-Julanda, Jayfar and 'Abd embraced Islam. Haudha b. 'Ali wrote back to say that he would accept Islam provided he was allowed to share the dominion with Muslims. The Prophet (Peace be upon him) turned down his request and he died soon thereafter.
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LETTERS TO MONARCH
The peaceful conditions following the Treaty naturally gave a boost to the missionary activities which kept on advancing day-by-day. Islam grew like an avalanche and showed the signs of assuming vast proportions. The Apostle then sent several letters to the rulers outside Arabia and the tribal chiefs (55) within the country inviting them to accept Islam. The letters were not couched judiciously by the Apostle but he also took care to select the envoys of different kings keeping in view the station and dignity of the different potentates. The envoys were conversant with the languages spoken as well as with political conditions of the countries to which they were deputed. (56)
Of the many letters sent by the Prophet (Peace be upon him), those written to Heraclius, the Emperor of Byzantine empire, Chosroes II, the Emperor of Iran, Negus, the king of Abyssinia and Muqauqis, the ruler of Egypt, are remarkably significant.
REACTION OF THE MONARCHS
Heraclius, Negus and Muqauqis received the letter from the Apostle with all due respect that each gave a courteous reply. Negus and Muqauqis showed the highest regard to the envoys from where the latter even sent some presents to the Apostle. These included two slave-girls, one of whom was Maria who gave birth to the Apostle's son Ibrahim.
Chosroes II was indignant, he tore the letter into pieces, saying, "My slave dares to write me thus!" When his reply was conveyed to the Prophet, he said, "even so shall God shatter his kingdom to pieces." (Tabari, Vol. III, pp. 90-91)
Heraclius decided to satisfy himself about the contents of the Apostle's letter. He ordered to search for a man from Arabia who could tell him about the Prophet. Abu Sufyan happened to be there on a business trip and so he was summoned before him. The questions raised by Heraclius on this occasion showed that he had a deep insight into the scriptures and the teachings of the prophet of yore and he knew how and when God sends them and the way they are usually treated by their people. Abu Sufyan, too, acted like a true Arab for he considered it below his dignity to tell the Emperor anything but truth.
THE EXPEDITION TO KHAYBAR
The reason to act against the Jews of Khaybar was that the Prophet decided that the time had come to get rid of their intrigues once and for all so that he might be able to divert his attention to other pressing matters.
It took place on the month of Muharam, 7 A. H.; Khaybar is situated at a distance of 180-Km northeast of Madinah.
The Muslim force that marched against Khaybar numbered 1,400 including 200 cavalries, 20 Muslims laid down their lives in the battle of Khaybar while they killed 93 of the infidels, the women and children was taken as captives.
The result of the battle was a great victory for the Muslims over their enemy, the Jews in Khayber and it's surroundings.
THE MISSED PILGRIMAGE
The following year, in 7 A.H., the Prophet (Peace be upon him) and his followers took the road to Mecca for performing the lesser pilgrimage missed by them earlier. The Quraysh thought it best to lock their house and retire to the heights of Jabl Qa'yqa'an overlooking the valley. (57) The Prophet (Peace be upon him) stayed for three days in the holy city and made the circuit of the holy house. Referring to the joyous event, the Qur'an says:
"Allah hath fulfilled the vision (58) for his Messenger in very truth. Ye shall indeed enter the Inviolable Place of Worship, if Allah will, secure, (having your hair) shaven and cut, not fearing. But He knoweth that which ye know not, and hath given you a near victory beforehand." [Qur'an 48: 27]
RIGHTS OF WOMEN RESTORED
Islam had changed the hearts and elevated the mentality of the Arabs. The custom which prevailed in the pre-Islamic days of burying female infants alive, so as to save the honor of the family, was not only given up but the daughters came to be so dearly loved that the people vied with one another in lavishing their affection to them. All Muslims, men and women, were equal, none-possessing any privilege over another; only he was superior who was better in morals and piety. When the Prophet (Peace be upon him) left Mecca after performing the 'Umra, the little daughter of Hamza known as Umama, followed him calling "Uncle, Uncle." Ali (may Allah be pleased with him) took her and asked Fatima to look after the girl.
Now Zayd and J'afar also claimed the guardianship of the child. 'Ali (may Allah be pleased with him) laid claim overr her since accordingly, she was the daughter of his uncle. J'afar on the other hand reasoned out that she was the daughter of his uncle and her maternal aunt was his wife.
Zayd, too, wanted to have the child for all the Muslims were brothers and he could very well look after the daughter of a deceased brother. The matter was brought to the attention of the Prophet (Peace be upon him) who decided that the maternal aunt being in the position of the mother of the girl should be given priority and thus the girl was finally entrusted to J'afar. To appease 'Ali, the Prophet (Peace be upon him) consoled him, "You are mine and I am yours." He then reassured J'afar by saying, "You resemble me in your looks and conduct." Zayd was also comforted with words, "You are my brother and client." (Al-Bukhaari)
EXPEDITION OF MU'TAH
The reason for the battle that the envoy of the Prophet to Sharhbil Ibn 'Amr al-Ghassani, a satrap of the Byzantine Emperor at Busra was killed. The guilt of blood had to be avenged with firmness so that no tyrant would be condemned to repeat a similar crime in the future.
It took place in Jumada Al-Ula, 8 A.H. Mu'tah is a village that lies on the borders of geographical Syria. It is 1,100 km north of Madinah. The Muslim force numbered 3,000 soldiers; the enemy's force was 200,000 soldiers of Romans and other tribes of Arabia. The killed people among Muslim's army didn't exceed 12 soldiers where it was too many on the other side. The result of the battle was that Khalid Ibn Al-Walid used a new strategy, which enabled him finally to retreat back to Madinah with the slightest losses.
In between the two major expeditions to Mu'ta and Makkah, some smaller ones were also undertaken. One of them was the raid of Dhat as-Salasil in the country of Khuza'a near Wadil-Qura, in Jamada-al-Ukhra, 8 A.H. The raiding party returned after smearing the enemy. Another raiding party consisting of 300 Ansaars and Muhaajirun was sent to chastise a clan of Juhayna. The army was enervated by hunger and had to live a few days on the leaves of the trees until God provided them a whale named 'Anbar' from the sea. The men feasted for fifteen days on the flesh and fat of the whale and regained their strength. They brought back a portion of it, which was taken by the Prophet (Peace be upon him) who said to the men, "It was sent by God for you." (59) This expedition goes by the name of Sif-al-Bahr and Khabat.