Human Being: Mankind As One Entity

The Quran reminds us that, originally, humankind was one ummah or entity , but this unity was broken by various differences which the human beings created among themselves -Quran Chapter 10 verse 19- It emphasizes the fact that the main purpose of sending God's message through various Messengers is to restore back the balance and unity of  humankind which once existed in the earliest period of human history -Quran chapter 2 verse 213 & Chapter  57 verse 25- The Quran warns us not to differentiate among Prophets -Quran chapter 2 verse 285 & Chapter 4 verse 136- because all of them came from the same source, which is Allah Almighty. But the followers of the Messengers (Peace upon all of them) not only created differences among the messengers but they also created divisions among themselves within the following of a single messenger. As other people, we the followers of Messenger Mohammad peace be upon him have also created divisions among ourselves. We have done this in spite of the very clear order of Allah Almighty to hold on to His rope together in unity and not be divided among ourselves  - Quran chapter 3 verse 101, 102, 103