Exodus 28
29 Ref And so Aaron will have the names of the children of Israel on the priest's bag over his heart whenever he goes into the holy place, to keep the memory of them before the Lord.
30 Ref And in the bag you are to put the Urim and Thummim, so that they may be on Aaron's heart whenever he goes in before the Lord; and Aaron may have the power of making decisions for the children of Israel before the Lord at all times.