Toward a Christian Understanding of Life after Death

I was recently asked to assist in a funeral at a church outside my own tradition. It was an interesting experience. Many things that were said and done gave me pause to think, but nothing caught my attention so much as the bold proclamation of the confident pastor: “The body in that box is not real. It’s just a shell. His spirit, his soul, that’s what’s real. That’s the real ‘him.’ That is what is forever, eternal, and it’s in heaven with God right now.”
I find this image of life after death, an image of disembodied spirits dwelling with God in heaven, to be a very popular understanding among many Christians, both in the pews and the pulpit. There’s one big problem, though: It isn’t biblical Christianity (despite its extreme popularity in circles who often make the loudest claims to be “biblical Christians”).
The image of life after death presented in the bible is clearly one of physical bodies resurrected from the dead to inhabit a renewed creation, a new heaven and a new earth. Far from this biblical image, what is touted by so many under the guise of Christianity is nothing more than a thinly veiled form of Gnosticism (N.T. Writght is very convincing on this issue). This gives rise to two questions on my part:
My first question: How did this happen? For centuries the Church fought Gnosticism at every turn, often forming clearer pictures of exactly what orthodox Christianity is by differentiating it from Gnostic distortions. Somewhere along the way Gnosticism seems to have abandoned frontal assaults for an apparently highly successful back door tactic. Where and when did this subversive tactic begin, and how has it been so effective as to practically dominate popular “Christian” thinking about life after death in our own day and time?
My second question: What can be done about it? I guess this question all boils down to how much are we willing to put up with a lie for the sake of the comfort it brings. Let’s face it: for many people it’s much more comforting to be told that Aunt Bettie’s spirit is in heaven making a big batch of her famous chocolate chip cookies, than to be told that Aunt Bettie is “asleep in Christ” for now, but that she will rise again at the resurrection when the fullness of the Kingdom comes. Does it really matter how much comfort something brings if it is a lie? Furthermore, are we willing to be branded heretics? For surely the Gnostic image of life after death is so thoroughly accepted by so many as genuinely “Christian” that any challenge to it will be met with furious resistance. Should it matter how much resistance we may face if we’re standing on the side of truth?
I don’t pretend to know the answers. I’m not so sure I’m the boat-rocking type. I do not relish upsetting Aunt Bettie’s loved ones, or incurring the wrath of the “righteous.” Besides, just who do I think I am anyway? All I know is that it’s gotten under my skin lately, and I’m a little concerned about what that might mean and where it might lead me.
Anybody out there have any thoughts?