And the skillfully woven waistband of the ephod must be of one piece, of the same workmanship—with gold, with blue, purple, and scarlet yarn, and with finely spun linen.
Directions are here given concerning the ephod, which was the outmost garment of the high priest. Linen ephods were worn by the inferior priests, Sa1 22:18. Samuel wore one when he was a child (Sa1 2:18), and David when he danced before the ark (Sa2 6:14); but this which the high priest only wore was called a golden ephod, because there was a great deal of gold woven into it.
Commenting on Exodus 28:6-14
And the curious girdle of the ephod, which is upon it,.... Which was worn along with it, and went out from it like two thongs, as Jarchi says, which girt the ephod close to the back and breast: shall be of the same; of the same matter as the ephod, and woven in the same manner, and together with it: according to the work thereof...
And the curious girdle of the ephod, which [is] upon it, shall be of the same, according to the work thereof; [even of] gold, [of] blue, and purple, and scarlet, and fine twined linen. (d) Which went about his upmost coat.