The ark of God was a sacred chest, made to be the depository of the Ten Commandments, which law was the representative of God Himself. This ark was considered the glory and strength of Israel. The token of the Divine Presence abode upon it day and night. The priests who ministered before it were sacredly consecrated to the holy office. They wore a breastplate bordered with precious stones of different materials, the same as compose the twelve foundations of the city of God. Within the border were the names of the twelve tribes of Israel, graven on precious stones set in gold. This was a very rich and beautiful work, suspended from the shoulders of the priests, covering the breast.
(SR 183.1)
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At the right and left of the breastplate were set two larger stones, which shone with great brilliancy. When difficult matters were brought to the judges, which they could not decide, they were referred to the priests, and they inquired of God, who answered them. If He favored, and if He would grant them success, a halo of light and glory especially rested upon the precious stone at the right. If he disapproved, a vapor or cloud seemed to settle upon the precious stone at the left hand. When they inquired of God in regard to going to battle, the precious stone at the right, when circled with light, said, Go, and prosper. The stone at the left, when shadowed with a cloud, said, Thou shalt not go; thou shalt not prosper.
(SR 183.2)
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