Peace be unto you, GST528i.
In the Name of God, The Most Gracious, The Most Merciful.

Originally Posted by
gst528i
3) Why is it okay for muslims to marry first cousins? (correct me if i am wrong please i do not mean to offend. It;s just i know muslims that are married and by their account they are first cousin.
Prophet Muhammad [s] said:
"God does not look at your body and face; rather he looks at your heart."(Sunan at-Tirmidhi)
In regards to marriage, he said:
"A woman is [generally] married for four reasons: her wealth, her family status, her beauty, and her religion. So you should marry the religious woman, otherwise you will be one of the losers!" (Sahih al-Bukhari)
So Muslims are encouraged to marry pious women of good character. If this person happens to be a cousin, then a man should marry her. However, there is nothing in Islam that encourages marrying cousins. Rather, it is solely based on piety.
In the West, cousins grow up together. Therefore, it is considered weird to marry cousins, since they are like brothers and sisters. However, under Islamic Law, when cousins hit the age of puberty, members of the opposite gender are separated and a strict code of gender segregation is followed. Women must cover themselves in the headscarf in front of male cousins, and for all intents and purposes, they are considered strangers. They don't even talk to each other, except perhaps a terse "as-salam alaykum" here and there.
As for why it is not forbidden, we don't see why it should be. Yes, it is true--proven by evidence based medicine--that consanguineous marriages (cousin marriages) increase the chances of certain diseases manifesting themselves. If inbreeding goes on for many generations, the increase in morbidity is significant.
The issue, however, is not really cousin marriages...rather, it is about inbreeding that goes on for many generations. In other words, an occasional cousin marriage here and there will NOT significantly increase the chances of disease manifestation. So why, reason Muslims, should we ban ALL cousin marriages?
So we believe that cousin marriages here and there are OK...inbreeding, on the other hand, is problematic.
Having said that, we *do* have the problem of inbreeding in many Muslim countries, such as Pakistan, i.e. first cousins keep getting married. This is contrary to our religion and it is a matter upon which many Ulema (clergy) are encouraging change. It actually doesn't have to do with religion, but tribal culture. They wish to keep wealth within the family and there are also racist reasons involved, reasons which are forbidden in Islam.
The motivations for inbreeding in Pakistan are against Islam, in my humble opinion. It is mostly a remnant of the Indian caste system which is contrary to Islam. It is very difficult to find a match because of the need to marry from the exact same caste. Furthermore, there is a desire to keep the money in the family. So, based on this greed and materialism, they seem to discourage what God has allowed, i.e. marriage to a non-relative. I also believe that many parents do not give their children the right to consultation in regards to whom they shall marry, which is also against Islam.
So to conclude the matter, inbreeding over many generations is a symptom of left-over jahiliyyah (Pre-Islamic culture), not of Islam. In Islam, we are to marry whoever is pious.
I certainly considered my cousin for marriage, although I decided against it. Not because she was my cousin, but for other reasons. But her being a cousin did not at all dissuade me from marrying her. I have no inbreeding in my family, so marrying her would not have caused any genetic problems.
Hope that helps.
In the Care of the Lord,
-Saladin.