Muhammad Quotes
Nobody should consider himself superior to another nor do him harm.
This concept of equality was perhaps the most radical and attractive aspect of the new religion of Islam in the 7th century when most of the world was hierarchical and the vast majority of people were in the lower classes. So Islam was a step up for almost all at the time.
Muhammad, 571-632, Prophet and Founder of Islam, Riyadh-us-Saleheen. Hadith 602
Sourced by: Eigen's Political and Historical Quotations
Muhammad was an Arab religious, social, and political leader and the founder of Islam. According to Islamic doctrine, he was a prophet, sent to preach and confirm the monotheistic teachings of Adam, Abraham, Moses, Jesus, and other prophets. He is believed to be the final prophet of God in all the main branches of Islam, though some modern denominations diverge from this belief. Muhammad united Arabia into a single Muslim polity, with the Quran as well as his teachings and practices forming the basis of Islamic religious belief.