THE BLESSED PLEDGE OF AL-GHADIR

Having finished his hajj to Mecca, the Prophet of Allah (s.a.w.) returned to Madinah and the great multitude of Muslims went back with him. At Ghadir Khum (brook of Khum) somewhere on his way to Madinah, he received the order of Allah to appoint Imam Ali bin Abi-Talib (a.s.) as his successor and the commander of the faithful after him.
Allah, the Most High, for some purpose only He knew, willed that this place should be where the Divine order would be communicated to the people.

The sun was slowly climbing in the sky and soon noon was approaching. It was a hot, sweltering day. It was so warm that when the Messenger (s.a.w.) stopped the Muslims to tell them Heaven's order, they began wrapping their feet with garments to ward off the heat of the gravel. It was the extra importance of the order, which by no means could be postponed, that made the Messenger (s.a.w.) halt, at that place and to deliver the new message.
He stopped them at crossroads from which they would go in different directions. Many of them would not see or hear the Messenger (s.a.w.) thereafter.

It was the last hour for many of the Muslims to see the Messenger (s.a.w.) and hear him telling them that Ali (a.s.), and only Imam Ali, would be their social and religious leader. It was the hour of good-bye and such an hour would be etched in one' s memory and so would be its implications. It had a distinguished flavour with deeply rushing sentiments. Had the Messenger (s.a.w.) delivered the news of the appointment of Imam Ali (a.s.), say 10 years earlier, the importance may have forgotten or it could have been subdued. But at the behest of Allah, he made it the last thing he communicated to his people so that it would live in the conscience of the ummah and remain alive in their memory.
He stood upon many mounts gathered for the purpose, so that all could have him in view. He praised and thanked Allah and said:

"O people! I am about to be called to Allah and depart to Him. I am responsible and so are you. What do you say?'

'We bear witness that you have delivered the Divine Message, fought for it and were faithful in guiding the people. May Allah reward you with His rewards,' they replied.

'Don't you,' he said,' bear witness that there is no god but Allah, Muhammad is His servant and Messenger, His paradise is right, His hell is right, death is right, resurrection day is right, the Hour would undoubtedly be coming, and Allah would raise people from the dead."

'We bear witness to these,' they said,

'O Lord! Bear witness,' he said.

Then he went on saying,:

'O people! Allah is my Master and I am the master of the faithful and I have a greater claim on them than they have on themselves. Whoever I have been his master Ali is also his master. O Allah! Befriend every friend of his and be the enemy of every enemy of his. O people! I will depart from you and you will certainly meet me at the Fountain: A Fountain that is wider than the distance between me and San'a' and has two goblets of silver as large as the space in which the stars are swimming. I will be asking you, when you return to me at the Fountain, about two weighty things: The weightier one is the Book of Allah, the Mighty and Glorified, which has two bonds, one is in the hand of Allah, the Most High, and the other in your hands. So hold tight to it, don't go astray and don't change your faith. The other mighty thing is my progeny, my household. The Knower of subtleties, the Aware has told me that they will join me at the Fountain as soon as their life on earth expires".(107)

Then he came down and offered a two-ruka'h prayer. His caller to prayer summoned the faithful and the Holy Prophet (s.a.w.) led his companions in prayer. Then he sat in his tent and ordered Imam Ali (a.s.) to go to his own tent.
He ordered the Muslims to give him their pledge as the successor of the Prophet (s.a.w.).
It was an unavoidable and necessary step on the part of the Prophet (s.a.w.) to enhance the prospects of the Islamic call.

THE ARMY OF USAMAH

The Messenger (s.a.w.) returned to Madinah to continue the march of construction and change. He was building the state and society and change man to be pious, chaste and benevolent in accordance with the Divine Law. The utmost priority for the Prophet (s.a.w.), after his return from Mecca, was to fight the Romans once more and he mobilized a tremendous army for this purpose.
In the army there were the dignitaries and the celebrated men from the Muhajirin (migrants) and the Ansar (Helpers) including Abu Bakr, Umar, Uthman and others.
Usamah bin Zaid bin Harithah, the young companion of the Prophet (s.a.w.) was appointed the leader of the army. But before the departure of the army the Prophet (s.a.w.) fell gravely ill.

References:
MUHAMMAD THE MESSENGER OF GOD PART ONE & TWO
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