Exodus 28:26
And thou shalt make two rings of gold, and thou shalt put them upon the two ends of the breastplate in the border thereof, which is in the side of the ephod inward. And thou shalt make two rings of gold, and thou shalt put them upon the two ends of the breastplate in the border thereof, which is in the side of the ephod inward.
Two rings of gold were to be put upon the two ends of the breastplate, in its border along the inner side beside the ephod. This is one specific detail in God's directions to Moses for the priests' garments, including Aaron's garments and the high priest's garments, for service in the sanctuary and holy place. The instruction fell from the lips of Jesus Christ, the great I AM enshrouded in the pillar of cloud, while educating His church in the wilderness.
The priestly clothing was to have a prescribed style suited to work in the holy place. The apparel of those who minister before God can honor or dishonor Him, and God requires order in everything and especially cleanliness, down to the detailed construction of priestly garments. Detailed care in appearance showed reverence for God and the holiness of the work for those serving in the sanctuary.
The breastplate belonged to the high priest's breastplate set with precious stones through which God made His guidance known to Israel and from which messages from Jehovah were received. The light of God's glory flashed upon those stones and the cloud of His disapproval shadowed them, by which His presence overshadowing the earthly mercy-seat was shown. The ephod and breastplate were not sacred in themselves, but their sacredness depended on being used in God's service as He had directed. Only the high priest was authorized to wear them when going before the Lord, which Gideon imitated when he made an ephod and breastplate from Israel's gold.
The breastplate and its attachment to the ephod are recalled in the heavenly sanctuary, where Jesus wears a glittering breastplate bearing letters like names engraved on it. That order ceased when Christ died. The veil of the temple was torn from top to bottom and the most holy place entered only once a year was revealed to common gaze, so no longer would God's presence overshadow the earthly mercy-seat and no longer would the light of His glory flash upon the stones or the cloud of His disapproval shadow them.
The priestly garments were symbolic, showing that the clothing of Christ's followers should also be symbolic and represent Him. The verse is part of God's expressed will and higher education giving the knowledge of the only true God and Jesus Christ whom He has sent. It is part of God's covenant with the people He seeks to save and the terms of salvation, and the education of most value for mental, physical, and moral improvement.