Wax seal
A blob of stamped wax closing a document — the old guarantee that the letter has not been opened by anyone else.
A wax seal in a dream is the dream's image of an old guarantee that a document has not been opened by anyone else. The seal is not the message; the seal is the promise about the message. The dream brings the wax seal when something in your life — a confidence, a sealed agreement, a private letter — is currently relying on a visible promise of untouched delivery. A wax seal arriving intact is the dream affirming that the promise has been kept. A wax seal arriving broken, with the wax scratched up, is the dream noting that the letter has been opened in transit, and the expectation of privacy that was built into the delivery has already been violated.