thummim the companion to the Urim in the high priest's breastplate

Exodus 28:30

And thou shalt put in the breastplate of judgment the Urim and the Thummim; and they shall be upon Aaron’s heart, when he goeth in before the LORD: and Aaron shall bear the judgment of the children of Israel upon his heart before the LORD continually.

Leviticus 8:8

And he put the breastplate upon him: also he put in the breastplate the Urim and the Thummim.

Deuteronomy 33:8

And of Levi he said, Let thy Thummim and thy Urim be with thy holy one, whom thou didst prove at Massah, and with whom thou didst strive at the waters of Meribah;

Ezra 2:63

And the Tirshatha said unto them, that they should not eat of the most holy things, till there stood up a priest with Urim and with Thummim.

Nehemiah 7:65

And the Tirshatha said unto them, that they should not eat of the most holy things, till there stood up a priest with Urim and Thummim.