1. Prophet's response to racist comments:
A man once visited the Prophet's mosque in Madinah. There he saw a group of people sitting and discussing their faith together. Among them were Salman (who came from Persia), Suhayb who grew up in the Eastern Roman empire and was regarded as a Greek, and Bilal who was an African. The man then said:
"If the (Madinan) tribes of Aws and Khazraj support Muhammad, they are his people (that is, Arabs like him). But what are these people doing here?"
The Prophet became very angry when this was reported to him. Straightaway, he went to the mosque and summoned people to a Salat. He then addressed them saying:
"O people, know that the Lord and Sustainer is One. Your ancestor is one, your faith is one. The Arabism of anyone of you is not from your mother or father. It is no more than a tongue (language). Whoever speaks Arabic is an Arab." (As quoted in Islam The Natural Way by Abdul Wahid Hamid p. 125)
2. Statement of the universal brotherhood in the last Sermon:
O people, Remember that your Lord is One. An Arab has no superiority over a non-Arab nor a non-Arab has any superiority over an Arab; also a black has no superiority over white, nor a white has any superiority over black, except by piety and good action (Taqwa). Indeed the best among you is the one with the best character (Taqwa). Listen to me. Did I convey this to you properly? People responded, Yes. O messenger of God, The Prophet then said, then each one of you who is there must convey this to everyone not present. (Excerpt from the Prophet's Last Sermon as in Baihiqi)
3. Don't take pride in ancestry:
The Prophet said: Let people stop boasting about their ancestors. One is only a pious believer or a miserable sinner. All men are sons of Adam, and Adam came from dust (Abu Dawud, Tirmidhi).
4. Looking down upon other people will stop you from entering the Jannah:
The Prophet said: Whoever has pride in his heart equal to the weight of an atom shall not enter Paradise. A man inquired about a person who likes to wear beautiful clothes and fine shoes, and he answered: God is beautiful and likes beauty. Then he explained pride means rejecting the truth because of self-esteem and looking down on other people (Muslim).
5. The Prophet condemnation of Arab racial pride:
There are many hadiths, which repeatedly strike on the Arab pride of jahiliyyah. Arabs before Islam used to look down upon others specially blacks. The Prophet repeatedly contrasted the believing Africans versus non-believing Arab nobles.