Exodus 28:37

37 And thou shalt put it on a blue lace, that it may be upon the mitre; upon the forefront of the mitre it shall be.

Exodus 28:37 In-Context

35 And it shall be upon Aaron to minister: and his sound shall be heard when he goeth in unto the holy place before the LORD, and when he cometh out, that he die not.
36 And thou shalt make a plate of pure gold, and grave upon it, like the engravings of a signet, HOLINESS TO THE LORD.
37 And thou shalt put it on a blue lace, that it may be upon the mitre; upon the forefront of the mitre it shall be.
38 And it shall be upon Aaron's forehead, that Aaron may bear the iniquity of the holy things, which the children of Israel shall hallow in all their holy gifts; and it shall be always upon his forehead, that they may be accepted before the LORD.
39 And thou shalt embroider the coat of fine linen, and thou shalt make the mitre of fine linen, and thou shalt make the girdle of needlework.
The King James Version is in the public domain.