Explanation of Riyadh al-Saliheen 6 Vol.

Generation after generation was destroyed by wars because a man would seek the aid of his tribe, even if he was upon falsehood and the likes of that from trivial causes and despicable motives. So Islam came to erase all of these loathsome outward practices in their lives when it made them equal with regards to the rights, and it made their slogans of allegiance to, al-Islam. And Islam made them excel over one another due to taqwa; (righteousness) and obedience to Allah. So there is no excellence for an Arab over a non-Arab, nor is there any excellence for a non-Arab over an Arab, nor for a white person over a black one, nor for a black person over a white one, except due to taqwa.