"Flee sexual immorality." 1Corinthians 6:12 - 7:7 is the full passage, but that verse pretty much sums it up. In the Greek, that verb is very strong. It means "run as fast as you can away from it."

Christians are to avoid sin in all forms, but especially sexual immorality because of how it affects people at a deeper level than other sins. There are 5 other passages in the Bible clearly stating that God includes homosexuality among the sexual sins.

It's pretty much impossible to participate in a same-sex wedding and not be seen as approving of the lifestyle it symbolizes. In participating, Christians not only negate their own witness in all other areas of morality, but they also hold the entire gospel up to ridicule. Why should anyone believe our faith message if our lifestyles are steeped in sin? The idea that we're not guilty of sin when we only condone it and are to doing the actual deed is a compromise with sin that you will not find anywhere in Scripture.