Brought forth by the Gentiles

So The Book of Mormon contains a prophesy about how in due time it would come to light via the Gentiles, but we know that Joseph Smith Jr. was a pure Ephraimite. How is someone who is totally an Israelite a Gentile? Bruce McConkie tried to clear things up by pointing out that Joseph wasn't from the tribe of Judah, therefore he qualifies as a Gentile. But the line being drawn in these verses is between the House of Israel and Gentiles, not Jews and Gentiles. The Lehites also qualify as Gentiles if we take Bruce's explanation and the scripture hardly seems to allow for that.

Thankfully there are a lot of other unofficial explanations out there from our more doctrinally-inclined membership. What are we to understand? Whatever the hell we want, except that this prophesy doesn't make much sense. Doubt that doubt. Doubt that Joseph wrote something about himself as a Gentile because it felt good and important, then years later forgot the specifics of what he wrote, and finally came around to telling people we was an Israelite because it felt good and important. You'll straighten things out eventually.