Ten years after the migration (hijrah), the Messenger of Allah (peace and blessings be upon him and his Progeny) asked his close followers to call all the people in different places to join him in his last pilgrimage. On this pilgrimage, he taught them how to perform the pilgrimage in a correct and unified form.

Iran PressIran News: This was the first time that the Muslims with this magnitude gathered in one place in the presence of their leader, the Messenger of Allah. On his way to Mecca, more than seventy thousand people followed the Prophet (PBUH). On the fourth day of Dhul-Hajjah, more than one hundred thousand Muslims had entered Mecca.

The date of this event was the 18th of Dhul-Hajjah of the year 10 AH (10 March 632 CE). After completing his last pilgrimage (Hajjatul-Wida'), Prophet (PBUH) was leaving Mecca toward Medina, where he and the crowd of people reached a place called Ghadir Khumm. It was a place where people from different provinces used to greet each other before taking different routes to their homes.

In this place, the following verse of the Qur'an has revealed:

"O Apostle! Deliver what has been sent down to you from your Lord; and if you don't do it, you have not delivered His message (at all); and Allah will protect you from the people ..." (Qur'an 5:67)

The last sentence in the above verse indicates that the Prophet (PBUH) was mindful of the reaction of his people in delivering that message but Allah informs him not to worry, for He will protect His Messenger from ill-wishers.

Upon receiving the verse, the Prophet (PBUH) stopped at that place which was extremely hot. Then he sent for all people who had been ahead in the way, to come back and waited until all pilgrims who fell behind, arrived and gathered. He ordered Salman to use rocks and camel toolings to make a pulpit (minbar) so he could make his announcement. On this day, the Messenger (PBUH) of Allah spent gave a long sermon.

The following is a part of his speech that has been widely narrated by the Sunni traditionists:

The Messenger (PBUH) of Allah declared: "It seems the time approached when I shall be called away (by Allah) and I shall answer that call. I am leaving for you two precious things and if you adhere to them both, you will never go astray after me. They are the Book of Allah and my Progeny, that is my Ahlul Bayt. The two shall never separate from each other until they come to me by the Pool (of Paradise)."

Then the Messenger (PBUH) continued: "Do I not have more right over the believers than what they have over themselves?"

Then he followed the key sentence denoting the clear designation of Ali as the leader of the Muslim ummah. The Prophet (PBUH) held up the hand of Ali and said: "For whoever I am his Leader (mawla), Ali is his Leader (mawla)."

He then continued: "O' God, love those who love him, and be hostile to those who are hostile to him."

Immediately after the Prophet (PBUH) finished his speech, the following verse of the Qur'an was revealed: "Today I have perfected your religion and completed my favor upon you, and I was satisfied that Islam be your religion." (Qur'an 5:3)

The above verse clearly indicates that Islam without clearing up the matter of leadership after the Prophet (PBUH) was not complete, and the completion of religion was due to the announcement of the Prophet's immediate successor. After his speech, the Messenger (PBUH) of Allah asked everybody to give the oath of allegiance to Ali (AS) and congratulate him.