Having a shallow tradition was all very fine until things stopped adding up for me. Acting on assumption “A” in my tradition brought me into direct conflict with assumption “B.” I remember a time at my church when I was asked to give a five-minute message on giving before taking up the evening’s offering. I drew on the teachings I was raised in and attempted to present a shorter version of a message I had heard in another church that I’d been a part of. It was a flop. I don’t remember much of what I said, except that after I’d finished, the pastor came up and took the microphone away from me and, half-jokingly said, “and now if you could just make your checks out to Kyle French…” Obviously something had gone wrong. *That* bit of background didn’t fit with *this* particular church. I resolved then never to say anything again that I hadn’t thoroughly reasoned out beforehand. (You have no idea how difficult this has made teaching Sunday School!)
Typically, I think, when a person comes to an impasse like this, and they discover that they really don’t know what they’re talking about, they normally take one of two options: The first is the coward’s way, which is to belligerently carry on as if nothing were wrong. You sort of bury your uncertainties and pick things up like nothing has changed. (“What about the germs?” I say. He goes, “I don’t believe in germs.”) The second option is to completely abandon your old understandings as thoroughly flawed and adopt another one out of whole cloth. This is a very brave thing, but I don’t know if it’s wise. I met a man last summer who had been raised a fire-and-brimstone Pentecostal, and is now a lay minister in the Orthodox Presbyterian Church. He believes his prior experience with spiritual gifts was entirely psychosomatic (for lack of a better word), and adamantly pushes for churches to adhere to “reformed worship’ which consists, among other things, of a complete abjuration of musical instruments. I couldn’t make that kind of switch. I don’t believe my former tradition was all stuff-and-nonsense. It was just… inconsistent. At the same time, I couldn’t just sweep the problems under the rug, since I wasn’t entirely sure which parts were the problems.
There is, of course, a third way, and I think it’s the hardest way of all, and that is to “test everything; hold fast what is good.” Keep your old theology, and listen carefully to other parts of the Christian faith that do it differently from you, particularly the ones that critique your way of doing it. Critique back. It may well be that your theology is correct in the main, and that there are only a few foreign parts that need to be weeded out. Or it may be that some other group has a better understanding of the whole picture, but they could sorely benefit from a few key insights that your background can bring to the table. Or, worst of all, you may discover that the closest approximation to “the way things work” is actually an integrated sampling from every group of Christians. This is bad because you won’t know what church to join.
neumatikos 
Of course the obvious question here is do you know which church to join?
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