Therefore...

Therefore, the holy Prophet moved with a fully equipped army that was very costly, towards the borders of Syria around the ninth of Hijrat. This he did because he wanted to personally command any kind of military encounter faced. The toil and trouble the Muslims had to undergo in this journey was compensated for, and proved to be constructive for the Muslim army which was able to recover its former dignity and thereby renew its political life.

The second adversary of Islam was the king of Iran 'Chosroe' who when read the Prophet's letter of invitation, was so much perturbed that he tore the letter disrespectfully and expelled the messenger's slave and even wrote the governor of Yemen to arrest the Holy prophet if not kill him.

Although the king of Iran 'Chosroe Parviz' died at the time as the Holy prophet, however, the subject of independence of yemen-, which was the colony of Iran, was not far from their perspective and the arrogance of the Iranian politics never allowed the tolerance of the existence of such a power. The danger lurking from the third side was the danger from the hypocrites that was continuously busy causing havoc and disruption through their hypocrisy among the Muslims.

This was to such an extent that they planned to kill the Holy prophet wanted to assassinate him on his way from 'Tabuk' to Madina. These were a group that used to be happy thinking that with the demise of the prophet of Islam, the whole of the Islamic movement will be terminated and rest will be in peace!

The destructive power of the hypocrites was such that the Holy Quran mentions in the chapters of Nisa, Maidah, Anfal, Baraat, Ankabut, Ahzab, Muhammed, Fateh, Mujadilah, Hadeed, Munafiqun and Hashr. Thus was it possible to think that the holy Prophet did not introduce a successor to control the religious, political and leadership for the newly established Islamic society considering all the dangers at lurk, not to mention the presence of these fierce enemies ambushing the Islamic state?