Exodus 28:7

It shall have the two shoulder pieces thereof
Which were two pieces that joined to the ephod, reaching from the arm holes to the shoulders both on the right and left, coming from before and behind; and meeting on the shoulders, were buttoned with two onyx stones, and covering the shoulders are called by this name:

joined at the two edges thereof;
the two edges of the ephod; not sewed thereunto with a needle, as Maimonides ^F23 and other Jewish writers think, but were woven along with it, and in the weaving was of the same with it:

and so it shall be joined together;
that is, the hinder and fore parts of the ephod in the shoulder pieces of it, shall be joined together by the two onyx stones upon them, hereafter mentioned, with which they were buttoned.