It is clear that Islam, undoubtedly, permits a man to marry any of his relatives except those forbidden for marriage whom Allah mentioned in surat an-Nisa’: 23.. Concerning the issue of preferring a marriage partner from within one’s family before choosing one from outside, this varies from one case to another. Islam is generally keen to widen the circle of social bonds.
Dr. Muzammil H. Siddiqi, former President of the Islamic Society of North America, states: “This list of preferences in marriage is not mentioned in the Qur’an or Sunnah. It is simply people’s own preference. It is up to you to follow it or not. Generally people prefer to marry people of their own kind. Marriages among people who are compatible to each other in family background, age, education, looks and habits are more successful. The Prophet (peace and blessings be upon him) said, “A woman is married for four things, i.e., her wealth, her family status, her beauty, and her religion. So you should marry the religious woman; (otherwise) you will be a loser.” (Reported by Al-Bukhari)
It is permissible to marry within your own family or relatives, and most people like that. However, as Muslims we must keep in mind that there are some relatives who are haram for marriage. These are mentioned in surat an-Nisa’: 23. Almighty Allah says: “Prohibited to you (for marriage) are: your mothers, daughters, sisters; father’s sisters, mother’s sisters; brother’s daughters, sister’s daughters; foster-mothers (who gave you suck), foster-sisters; your wives’ mothers; your step-daughters under your guardianship, born of your wives to whom you have gone in, no prohibition if you have not gone in; (those who have been) wives of your sons proceeding from your loins; and two sisters in wedlock at one and the same time, except for what is past; for Allah is Oft-Forgiving, Most Merciful.”
It is also forbidden for Muslims to marry non-Muslims. The only exception is that a Muslim male is allowed to marry a chaste woman from among the People of the Book, i.e. Christians or Jews (see al-Ma’idah: 5).
It should also be remembered that forced marriages are not permissible in Islam. Parents should never force their sons and daughters to marry someone against their will This is haram and it causes many social problems. Parents should advise their children and likewise children should take their parents’ advice seriously, but finally it is the will and consent of those who are getting married that should prevail.”