'Urim' in the Bible

Then Saul said, "O Lord God of Israel! If this sin has been committed by me or by my son Jonathan, then, O Lord God of Israel, respond with Urim. But if this sin has been committed by your people Israel, respond with Thummim." Then Jonathan and Saul were indicated by lot, while the army was exonerated.

And when Saul inquired of the LORD, the LORD answered him not, neither by dreams, nor by Urim, nor by prophets.