Exodus 28:36-38

BBE(i) 36 You are to make a plate of the best gold, cutting on it, as on a stamp, these words: HOLY TO THE LORD. 37 Put a blue cord on it and put it on the front of the twisted head-dress: 38 And it will be over Aaron's brow, so that Aaron will be responsible for any error in all the holy offerings made by the children of Israel; it will be on his brow at all times, so that their offerings may be pleasing to the Lord.