Gay Marriage

Sodom and Gomorrah was a gay city that got wiped by the Lord for being gay.
Leviticus 18:22 - "Do not lie with a man as one lies with a woman; that is detestable." (NIV)
Leviticus 20:13 - "If a man lies with a man as one lies with a woman, both of them have done what is detestable. They must be put to death; their blood will be on their own heads." (NIV)

Unless you're Jewish Leviticus has virtually no meaning to you. Christ changed the rules for Christians and the Muslim's have their very intricate and much more thorough beliefs on the subject than the two paltry references you were able to scrape out of the depths of transliterated antiquity there. I won't even dignify Sodom and Gomorrah except to say you've either misunderstood that section, or were took guidance on it from someone with an agenda.

The closest word for one who picks and chooses which aspects of a religion to encourage based on their own agenda would be hypocrite.
If any portion of these laws, supposedly the absolute will of god, are capable of being considered out-dated they are all equally fallible, otherwise they should all continue to be adhered to with equal fervor, not simply pulled out to excuse or justify bigotry. That's been done against slaves, women and countless other minorities for time immemorial.

• You are not to take a woman to be a rival with her sister and have sexual relations with her while her sister is still alive.
  
• You are not to approach a woman in order to have sexual relations with her when she is unclean from her time of her period.
  
• You are not to go to bed with your neighbor's wife and thus become unclean with her.
  
• Do not plant your field with two kinds of seed.
  
• Do not wear clothing woven of two kinds of material.
  
• Do not cut the hair at the sides of your head or clip off the edges of your beard.
  
• Rise in the presence of the aged, show respect for the elderly.
  
• When an alien lives with you in your land, do not mistreat him. The alien living with you must be treated as one of your native-born. Love him as yourself, for you were aliens in Egypt.
  

My personal favorite;
'Do not be unjust in judging - show neither partiality to the poor nor deference to the mighty, but with justice judge your neighbor. "