My good friend, Dan Fabricatore, has left a short, but excellent post on his blog, "God Incarnate: Thoughts on Christ, his church, and pastoral ministry." Here is my affirmation and response.
If I understand you correctly, I agree completely. If people believe incorrectly, they will behave incorrectly. And if they behave incorrectly (i.e. sin), they will become spiritually dull and have a decreased capacity to understand and accept more difficult truth. Oh, they might understand the flow of the argument simply because they can understand the grammar and syntax, but they will not accept the difficult truth as genuine since, "that just can't be true."
Every pastor has heard this. They preach a solid exegetical message, deliver an appeal for the individual to amend their sinful life and then be faced with "Well, I know what you said, but I disagree."
"Why? Did I misunderstand the text? What do you think I misinterpreted?"
"Well, I don't know, but that just can't be right. What you said sounds all well and good, but you've got to live in the real world."
Believing in the resurrection of the dead isn't, in the most basic sense, living in the "real world," defined as the world of my limited experience. All people know that the dead don't return to life. I've never seen it, nor has any of my friends. I've never read about it in any recent history books, you know what I mean, the kind that recorded "real" history instead of confusing myth and reality. Back in the days of the NT, those people were so superstitious that they could have easily been fooled. So you just can't trust such a fantastic tale from such an unreliable time. Right?
Wrong. They knew that people didn't rise from the dead, just as we do. They'd never seen it. And when it was claimed that someone rose from the dead, people from all over flocked to see the oddity. (John 12:17-18) It was just as difficult to believe then as it is now. It isn't from the "real" world. That's why Paul had to be so careful to lay the foundation of corrected living, so that readers would be able to accept this outrageous claim.
That's also why preachers today have to be ever vigilant to call their congregations to right thinking and right living. Otherwise the difficult but wonderful truths will be paid lip service, but not really believed to the point that it changes our lives.