While, as with most Christian doctrines, groups and individuals have differed on this or that point, sometimes sharply, most Christians have historically believed that each human individual has — or, more accurately, is — a unique soul. This soul, once it begins to exist, is permanent. That is, it will not be destroyed. It constitutes the person's identity and, at death, continues to exist in a disembodied state until the resurrection.
It's sometimes said (and I agree) that mastering a foreign language teaches a great deal about one's own. Similarly, I think, learning about other faiths can help us to understand ours, just as contrasts of shades and colors help us to see more clearly. Here's an example:
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