Book of Mormon Central: KnoWhy

How Was Mosiah a Type of Christ? (1x104)

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While it is not possible to determine absolutely the origin of the name Mosiah, of whether Mosiah was the given name or title of these two Nephite leaders, it is not at all implausible to see it as deriving from the Hebrew word môšiaʿ. In fact, in the absence of any better alternate propositions, this appears to be the strongest theory.