Newsflash- the Judeo-christian tradition goes back further than Jesus, so does the institution of marriage.
But in all seriousness, in my opinion, gays should be able to marry.
If a particular church won't marry them, so be it.
The problem I have with opposition to prop 8 is that it was decided democratically. Now, there have been many other issues that we feel are wrong nowadays that were decided democratically in the past (see slavery), and I certainly don't feel that those were correct simply because they were democratic in nature. However, there are states in the U.S. where gay marriage is legal. Gays as well as straights can move around the U.S. as they please. If they desire to move to another state to be wed or simply to be in a more gay friendly community, that is fine.
Because we decide things democratically, when decisions are made we are subject to those decisions by virtue of the fact that we live in the U.S.
California's decision on Prop 8 was going to affect all of those in the gay community in California. The gay community knew this. They recognized that this would affect them profoundly. Could they have done more to sway voters? Probably. Would it have helped? Who knows. However, the gay community in California will be subject to the decisions passed down by the votes. That's just how it is. If they don't like it, they can protest, which often does nothing, or move.
Again, I think allowing gays to marry should be legal by law and it should be at the church's discretion who they wed. Remember, you can be wed by a justice of the peace.
Anyway, kind of a rant, hopefully I made some good points, maybe not.