"Every church has a different opinion on the issue"

Well, see, that is the problem. Truth and morality are not defined by individual churches but by God. The authentic Church has not "evolved" on this issue for nearly 2000 years. So what changed?

Not Jesus Christ.
Not Scripture.

Not the laws of hermeneutics.
Not orthodoxy.
Not orthopraxy.
Not the Sanctity of Marriage.
Not creeds.
Not Church documents and statements of faith (until the last few years, of course).
Not the epistles.
Not objective truth.
Not objective morality.
Not moral law.
Not even natural law.
...
And, finally, not man's desire for selfish sin and to gain autonomy from his Creator.

So, what's changed? Nothing! Except of course, some "churches" who think they can keep their collection plates full by following man instead of God.