Holy Prophet Muhammad (S.A.W.) and his Universal Message
Theologically speaking, the universality of Prophet Muhammad's message ,peace and blessings be upon him, comes from the concept of one God who is the God of all, not only the God of Muslims. God describes Himself in the first chapter of the Qur'an, which is recited by all Muslims around the world in their five daily prayers; He is the God of all creation, "Rabb al-Alamin." Whether humans are aware of this fact or not, Allah is the creator of all mankind i.e.Muslims, Christians, Atheists and Hindu.
Regardless of their differences. God is the creator of everything, with no exception. The Qur'an declares that a gigantic star and an atom are shoulder to shoulder, worshipping the same God; a fly and an elephant are brothers and sisters; all of creation is here to help us understand the meaning and the mystery of the universe.
The message brought by Muhammad (Peace be upon him and his family) is the last prophet of Allah for man kind. For this it was natural for his prophet hood to be universal. Unlike Hazrat Muhammad (S.A.W.) earlier prophets were sent for limited periods & areas. Though, the basic message of all the prophets of Allah was same.
Universality of Prophet Muhammad's prophet hood is also declared by Quran in categorical way by various ayahs, for example:
Say: O people! I am sent unto you all, as the Messenger of Allah, to whom belongs the dominion of the heavens and the earth: there is no god but He: It is He that gives both life and death.
Similarly Quran says: We have not sent you but as a universal (Messenger) to people, giving them glad tidings, and warning them (against sin) but most people understand not.
When we consult the Quran, the last revelation of Allah for mankind, we always observe that the address is to whole of man kind, In Quran many times it has been said Oh! The mankind The teachings of the prophet and approach he adopted also have made it quite clear that his prophet hood is for all the people and nations of the world.
The Prophet had declared clearly that he has been sent as Prophet for all the people of the world, black and white, Arabs and non-Arabs. The last Hajj performed by the prophet and the sermons delivered during it stands prove for it as in those sermons the prophet has addressed all the mankind and advised those who were present to convey his message to the rest of the world.
After the peace was reached with Quresh by prophet, at Hudabiya, the messengers were sent to far filing countries and their rulers.
Allah sent his last revelation to the last prophet in a language which is learnt and taught till now and will last till the Day of Judgment. Thus Allah made an arrangement to preserve his last revelation and the teachings of his last prophet.