A mechanical barrier recipient verification system including a combination lock assembly having a housing carrying a combination lock mechanism. The housing forms an aperture. The lock mechanism selectively receives and captures a post inserted through the aperture. Further the lock mechanism is configured to provide combination unset and set states; unlocked and locked positions; and correctly and incorrectly entered code arrangements. Following insertion of the post into the aperture and with the lock mechanism in the locked position, the post is retained by the lock mechanism regardless of the correctly or incorrectly entered code arrangement.