Full Idea
If a speaker introduced a designator into a language by a ceremony, then in virtue of his very linguistic act, he would be in a position to say 'I know that Fa', but nevertheless 'Fa' would be a contingent truth (provided F is not an essential property).
Gist of Idea
The very act of designating of an object with properties gives knowledge of a contingent truth
Source
Saul A. Kripke (Naming and Necessity preface [1980], p.14)
Book Reference
Kripke,Saul: 'Naming and Necessity' [Blackwell 1980], p.14
A Reaction
If someone else does the designation, I seem to have contingent knowledge that the ceremony has taken place. You needn't experience the object, but you must experience the ceremony, even if you perform it.