Exodus 28:12

28:12 You are to put the two stones on the shoulders of the ephod, stones of memorial for the sons of Israel, and Aaron will bear their names before the Lord on his two shoulders for a memorial.

Exodus 12:14

12:14 This day will become a memorial for you, and you will celebrate it as a festival to the Lord – you will celebrate it perpetually as a lasting ordinance.

Exodus 39:7

39:7 He put them on the shoulder pieces of the ephod as stones of memorial for the Israelites, just as the Lord had commanded Moses.