And you shall put it on a blue cord, that it may be on the turban; it shall be on the front of the turban.
Exodus 28:37
Surrounding context
28:36 "You shall also make a plate of pure gold and engrave on it, like the engraving of a signet: HOLINESS TO THE LORD.
28:37 And you shall put it on a blue cord, that it may be on the turban; it shall be on the front of the turban.
28:38 So it shall be on Aaron's forehead, that Aaron may bear the iniquity of the holy things which the children of Israel hallow in all their holy gifts; and it shall always be on his forehead, that they may be accepted before the LORD.