six of their names on one stone and the remaining six on the other, in the order of their birth.
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
Six of their names on one stone,.... The names of the six eldest on the stone upon the right shoulder: and the other six names of the rest on the other stone: the names of the six youngest on the stone upon the left shoulder; for these stones, as afterwards said, were put on the shoulders of the priests: according to their birth; the order...
Six of their names on one stone, and [the other] six names of the rest on the other stone, according to their birth. (e) As they were in age, so should they be graven in order.