What Was In The Stone Box?
Revelation given through Joseph Smith the Prophet to Oliver Cowdery, David Whitmer, and Martin Harris, at Fayette, New York, June 1829, prior to their viewing the engraved plates that contained the Book of Mormon record.
“Behold, I say unto you, that you must rely upon my word, which if you do with full purpose of heart, you shall have a view of the plates, and also of the breastplate, the Sword of Laban, the Urim and Thummim, which were given to the brother of Jared upon the mount, when he talked with the Lord face to face, and the miraculous directors which were given to Lehi while in the wilderness, on the borders of the Red Sea.” (Doctrine and Covenants 17:1)
<< Golden Plates, Urim & Thummim...Breast Plate. by David A. Baird, & Edit by Phil Michel
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Note: There are many scripture in the Bible that refer to a breastplate and the Urim and Thummim that were given to Prophets to use.
"And he put the breastplate upon him: also he put in the breastplate the Urim and the Thummim." (Leviticus 8:8)
"And they made two rings of gold, and put them on the two ends of the breastplate, upon the border of it, which was on the side of the ephod inward." (Exodus 39:19)
"And he put the abreastplate upon him: also he put in the breastplate the bUrim and the Thummim." (Leviticus 8:8)
"A passage in the Book of Exodus describes the Ephod as an elaborate garment worn by the high priest, and upon which the Hoshen, or breastplate containing Urim and Thummim, rested." (Wikipedia, 2017)