It is reported that the Prophet Muhammad (pbuh) said: I saw myself (In a dream) following a herd of black sheep. Then a group of white sheep came (and mixed with the black sheep) until they (the white sheep) became so many that the black sheep could no longer be seen in the herd of sheep." Abu Bakr, the companion of the Prophet (pbuh) and the interpreter of dreams, said, "O Messenger of Allah. As for the black sheep, they are the Arabs. They will accept Islam and become many. The white sheep are the non-Arab Persians, etc.