28 They are to fasten the rings on the breast piece to the rings on the ephod with a blue cord so it will rest on the skillfully woven band of the ephod and so the breast piece won’t come loose from the ephod.
Exodus 28:28 Cross References - ISV
Exodus 28:31
31 Other Garments for the Priests“You are to make the robe of the ephod entirely of blue.
Exodus 28:37
37 You are to put it on a blue cord and place it on the turban. It is to be on the front of the turban
Exodus 39:30-31
Numbers 15:38
38 “Tell the Israelis that they are to make tassels at the edges of their garments throughout their generations and that they are to put a violet cord on the tassels at the edges of their garments.