Epigraph: Allah has promised to those among you who believe and do good works that He will surely make them Successors in the earth, as He made Successors from among those who were before them; and that He will surely establish for them their religion which He has chosen for them; and that He will surely give them in exchange security and peace after their fear: They will worship Me, and they will not associate anything with Me. Then whoso is ungrateful after that, they will be the rebellious. (Al Quran 24:56)

World Leader of Ahmadiyya Community, His Holiness Mirza Masroor Ahmad in Capitol Hill, USA in June 2012. He is seated in the middle, to his right is Ameer of USA, Dr. Ahsanullah Zafar and to his left Congressman Keith Ellison and Ex. Speaker Nancy Pelosi and Congressman Mike Honda is speaking at the rostrum

As the prophets of God have a limited time span, for a long term mission Allah proposed the institution of Khilafat.

After Prophethood, Khilafat is the most important institution in Islam. Khalifas are ultimately appointed by God through His Divine guidance. Though Khilafat had disappeared, it has been re-established as prophesied by The Holy Prophet, Muhammad, may peace be on him.  Read further in Alislam.

The Founder of the Ahmadiyya Muslim Community, the Messiah, Mirza Ghulam Ahmad Qadiani, said about Khilafat or the second manifestation:

Allah’s Divine Power is manifested twice. I appeared from God as a manifestation; I am a personified power of God; and after me there shall come other persons who will be the second manifestation of Divine Power.

The Holy Prophet Muhammad, may peace be on him and after him Umar Farooq, the second Khalifa of Islam were the main pioneers in the human society of pluralism, multiculturalism and religious tolerance. As such they laid the foundations of United Nations of the Latter days. These values did not exist before them to any significant degree! Religious tolerance is not a human invention but a divine prescription. For details of pluralism and multiculturalism and religious tolerance read the section on Umar Farooq, in August 2008 Alislam-eGazette and Caliph Umar Farooq versus Emperor Heraclius: Who gave us our Religious Freedoms?

It had to be so as the previous prophets had a limited scope whereas the scope of the Holy Prophet Muhammad was universal and timeless. 

Complete unification of nations was destined to occur under the banner of the Prophet Muhammad, may peace be upon him, in the time of the Messiah, the Founder of the Ahmadiyya Community.

The Messiah, who is also referred to as the Promised Messiah, wrote about religious and moral victory of Islam over other religions and ideologies: 

The era of the prophethood of the Holy Prophet has been decreed to last until the final days. He is the Seal of all the Prophets. It is for this reason that God did not wish for the complete unification of the worlds nations to occur in his lifetime, for this would have implied the end of his epoch. That is to say, it would have raised doubt that the age of the Holy Prophet had come to an end because the final task would have been completed. Thus, God decreed that the task of unifying the world’s nations around one religion be completed towards the end of the era of the Holy Prophet, the time when Judgment Day is at hand. God chose a successor from amongst those who followed him to accomplish this and named him the Promised
Messiah. He has also been referred to as the Seal of the Khulafa.
The Holy Prophet came at the beginning of the Muhammadan era and the Promised Messiah has appeared at its end. It was essential that this age would not come to an end until his advent. The unification of nations is closely associated with his
time. The Holy Qur’an has hinted at this in the verse (61:10), ‘That is, God is He, who has sent His prophet with complete guidance and a true religion, so that He may make him emerge triumphant over all other religions and bestow him with universal victory.’

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All those scholars who have come before us, have been agreed on the fact that this universal victory will occur in the time of the Promised Messiah. (Promised Messiah in Chashma Ma’rafat, Ruhani Khazain, Vol.23. p. 82-83)

Read further about Khilafat in August 2008 volume of Alislam-eGazette, which was about Khilafat Centenary Celebrations.

Additional Readings about recent achievements of Khalifatul- Masih V, His Holiness Mirza Masroor Ahmad

World Crisis and the Pathway to Peace

Video of Keynote Address at Capitol Hill in USA by Khalifa of  Islam

Khalifa of Islam delivers ‘a powerful and inspiring address,’ in  EU Parliament

World Muslim Leader says new Mosque will spread Peace and Unity  in Spain

Ahmadiyya Muslim Community making History in Los Angeles