Sure, churches change. In the 19th Century, many churches in the south found support for slavery in the Bible. Those passages are still there. How do you interpret them?
In the 10th Century, all the churches believed the Bishop of Rome was the head of the whole shurch, today many do not.
Even the definition of adultery is flexible. The 'Orthodox Church in America' (TM) has a liberal attitude towards divorce. They define career obsession as a form of adultery and legitimate grounds for divorce. Where does it say that in the Bible? And that is considered to be a 'conservative church.'
Many of todays Churches have in fact altered their doctrine to allow America's most affluent minority into the fold.
Yes, and that minority (or maybe majority) is made up of adulterers and fornicators.