explanations of incense
Your reaction to an explanation of incense which is different from what the good nuns gave out is not what mine would be. Symbolism is not a zero-sum game; they operate on various levels and all may be equally valid at the same time. What happens in very many cases is that a custom arises from a humdrum and everyday usage or practice. As times change and there is no longer a practical reason for keeping it up, there is the usual human reaction to go on doing the same thing, so people tend, consciously or unconsciously, to find a justification to keep on doing the same thing the same way. And if you have a really inventive fellow around, (like St. Thomas Aquinas, among others) you can assign a symbolic meaning. Hence, when there was no longer need for incense as air freshener, its symbolic meaning equating it with prayers (which had been present all along -- it's mentioned in the Psalms in this context, among other places) became the sole meaning and the former use was relegated to history.
