This reminds me of what was done in England during the time in World War II when invasion by the Nazis seemed imminent. The English took down all road signs so that the invading Nazis would not have any idea about where they were or where they were going. They are the water and its sprinkling, the bread and its eating, and the wine and its drinking. They all point to Christ and our salvation by way of His death upon the cross and His resurrection from the grave. The sacraments, in other words, direct our attention towards Christ and what happened on Good Friday and Easter Sunday as the only way of salvation.
Sacraments are also visible seals.
Seals are used on documents like birth certificates, marriage licenses, driver's licenses, Last Wills and Testaments, Living Trusts, and every other sort of official document. A seal authenticates or certifies these document as being real and genuine and true. Seals are also given to persons. When Pharaoh made Joseph the second most powerful man in Egypt, Joseph was given Pharaoh's seal or signet ring. They seal to us the reality of our salvation in Christ through His blood and Spirit.