I hear it all the time:
“Christians in years to come will be just as ashamed over the Church’s opposition to same-sex marriage today, as we are now about slaveholders in the South using the Bible to support slavery.
So very wrong: and yet so close to the truth. I’ll explain why.
First, here’s what’s wrong in it. It’s what I call an argument from future opinion:
We ought not do x today because in the future we’ll find out that x was wrong.