1. Right vs. privilege: Gay activists talk about the "right" to get married. Yet in the next sentence they talk about obtaining a marriage license. Marriage is a privilege, not a right. Therefore, the state must have a standard for issuing a license. We don't give a license to anyone who wants to drive a car. You must know basic information and demonstrate an ability to drive. We don't grant a medical license to just anyone. Someone must demonstrate a level of competence. Marriage isn't a right, it is a privilege that the state can and should regulate.
If marriage is a privilege it's one that's awarded to all hetrosexuals (of consentual age) - what basic information and ability do they have possess? The ability to perform sexual intercourse??? Not even that, it's not like they make you sit a test.

2. Devalues marriage: Giving same-sex couples the right to marry devalues true marriage. Imagine if at the next awards ceremony, everyone received an award. Would anyone value the award if everyone received one? Any adult is permitted to marry another adult of the opposite sex. But you can't marry a child, you can't marry a blood relative, you can't marry someone already married, you can't marry someone of the same sex.
People have been devaluing marriage forever, divorce rates show that.
You can't marry a child because we have age of consent laws to protect children.
Marrying a close blood relative is incestuous but depending on the closeness there are exceptions made.
Marrying someone who is already married is Bigomy.

3. Basic biology: Homosexual relations deny the self-evident truth that male and female bodies complement each other. Human sexuality and procreation is based upon a man and a woman coming together as one flesh. Marriage between a man and a woman promotes procreation and makes intimate sexual activity orderly and socially accountable.
Male and female bodies are compatible for intercourse to conceive children.
Procreation doesn't need promotion.
Who wants "orderly" sexual activity ??? ~lol~
I know plenty of married couples who are socially unaccountable.

4. Public health: Homosexual sex is dangerous and destructive to the human body. The International Journal of Epidemiology reports that the life expectancy at age 20 for gay and bisexual men is 8 to 10 years less than for all men. If the same pattern of mortality were to continue, researchers estimate that nearly half of gay and bisexual men currently 20 years of age will not reach their 65th birthday.
I never heard that before - provide documented proof
I would have thought that homosexuals had more to fear from random acts of homophobic violence.

5. Counterfeit: Arbitrarily granting a marriage license to a same-sex couple doesn't constitute marriage. It is a counterfeit of true marriage. It is like trying to tape two same-sex electrical plugs together to form an electrical current.
Granting a marriage license to anybody doesn't constitute a marriage. Two people coming together in love and respect is what constitutes a marriage.

6. Monogamy/fidelity: Same-sex marriage will not be monogamous. One lesbian writer calls gay marriage "monogamy without fidelity." Another homosexual columnist writes of "a broader understanding of commitment." A recent Dutch study found that homosexual relationships last, on average, about 1-1/2 years and that men in those relationships have an average of eight partners per year outside their main partnership.
Hetrosexual marriages are not guaranteed to be monogamous either. My sister in-law has been with her partner for 20years - you can't generalise about people in that way.

7. Children: Marriage between a man and a woman is the ideal family unit. It promotes procreation and ensures the benefits of child rearing by the distinct attributes of both father and mother. Two research papers by Timothy Dailey for Family Research Council (Homosexual Parenting: Placing Children at Risk and Homosexuality and Child Sexual Abuse) document concerns about children raised in gay marriages.
The ideal family unit is one where children are raised in love and safety, whether that be with same sex parents, hetro parents, grandparents, whoever.

9. Majority rule: A recent poll by the Pew Forum on Religion and Public Life found that public opposition to gay marriage is increasing. In July, 53 percent opposed same-sex marriage. By October 59 percent were opposed to same-sex marriage.
Terrible isn't it
Where's the love, the compassion, the tolerance?????
Who raised these people???

10. Popular vote: States legislatures have already spoken to the issue of same-sex marriages. Thirty-seven states have already passed a Defense of Marriage Act (DOMA) stating that marriage is between a man and a woman. In 1996 Congress also passed a national DOMA.
Hopefully things will change.

11. Religion: The Bible teaches that homosexuality is not natural and is wrong (Romans 1:26-27, 1 Corinthians 6:9-10). Other religions also concur with this judgment.
I can't be arsed to answer this tired old 'pull outta the bag as needed' crap.

12. Emotional: Gays and lesbians are relationally broken people. Just as in heterosexual marriage, two broken people cannot produce a whole, healthy unit. However, heterosexuals can get help for their brokenness and repair the relationship, but the relationships of homosexual couples are intrinsically and irreparably flawed.
Intrinsically and irreparably flawed eh?
Widespread discrimination and generalisations are always helpful