In D& 95:7, "Lord of Sabaoth" is interpreted by Joseph Smith as being "the creator of the first day, the beginning and the end."
In an insightful article, Lord of Sabaoth, John Tvedtnes wrote, in part:
A third- or fourth-century AD Jewish copper amulet found near Kibbutz Evron, Israel, has a Greek inscription that speaks of “the One who made the heavens and founded earth and established sea <and> who made everything, Iao Sabaoth” [Jehovah of Sabaoth], confirming the meaning.
The reference for this is the following:
Roy Kotansky, Greek Magical Amulets: The Inscribed Gold, Silver, Copper, and Bronze Lamellae Part I, Papyrologica Coloniensia 22/1 (University of Cologne, Germany, and Westdeutscher Verlag, 1994), 314.
Fortunately, Roy Kotansky has made this book available online on Academia.edu. Here is the Greek of the amulet, taken from p. 314 (I have highlighted the relevant text from the Greek):
While some critics believe that the interpretation of Lord of Sabaoth in the Doctrine and Covenants is a linguistic error in LDS Scripture (e.g., Richard Packham), in reality, it is another "hit" in favour of the authenticity of Joseph Smith's revelations.
For another useful article on this issue, see:
Matthew L. Bowen, “Creator of the First Day”: The Glossing of Lord of Sabaoth in D&C 95:7