Why was the message of Prophet Muhammad (ﷺ) preserved?
The message that changed the world is the message of tawheed. It is the message, which was taught to Adam (عَلَيْهِ السَّلاَمُ), the first human being, which changed its world. And every prophet, around 124,000 prophets, sent to all nations in the world so that the message continued to change the world in each era of human history.
With Prophet Muhammad (ﷺ), the message was now preserved in such a way that it would never change. The earlier messages which changed the world in the area in which the prophets were sent, those messages have changed. And even the prophets who brought them, their names are now lost. We just know in general because Allah told us in the Qur’an:
“I have sent in every nation a messenger calling people to worship Allah alone and to avoid worship of false God…” 
This essential message has been preserved in Islam in a way that it was never preserved before. It was not because of the difference of the messages; the message is still the same, but because of the fact that there will be no other prophet who will come after Muhammad (ﷺ). Therefore, that message had to be protected and had to be preserved in a way none of the earlier messengers were preserved.
Prophet Muhammad (ﷺ) left for us a blueprint as to how that message should be conveyed. He left the message, first and foremost. He was an example of the effect of the message on a human being. And his example was preserved with such detail that anyone today who wants to know that message, in its entirety with all of the details, he/she has access to it. And this is how it will remain until the last day of this world. Even when Prophet Isa, Prophet Jesus (عَلَيْهِ السَّلاَمُ) comes back, he will not come back with new message or a new interpretation of the message. He will come back following and teaching the same message. And that was what Prophet Muhammad (ﷺ) told us. At that time, when Prophet Isa (عَلَيْهِ السَّلاَمُ) joins the prayer in Jerusalem, Baitul Maqdis, and Imam Mahdi is going to lead the prayer, and when Imam Mahdi realizes that Prophet Isa (عَلَيْهِ السَّلاَمُ) has joined the frontline of the prayer, he wants to step back and allow Prophet Isa (عَلَيْهِ السَّلاَمُ) to lead, but Prophet Isa (عَلَيْهِ السَّلاَمُ) will stop him and send him back to lead the prayer.
 [Qur’an 16:36]< Back to Questions