The phrase "the core message of" is a grammatically correct part of a sentence and can be used in written English.
For example, you could use this phrase in the sentence, "The core message of the speech was the importance of working together."
That is the core message of hip-hop right there.
But it was the core message of the speech that marked Obama out as a kindred spirit.
"The core message of GLF was that genuine queer emancipation involves changing society, rather than adapting to it.
The core message of our findings is simple: Talk to your baby whenever you get the chance — and whichever direction your stroller faces.
Mr. Gibson said in a statement: "Anti-Semitism is not only contrary to my personal beliefs; it is also contrary to the core message of my movie.
One area where he does not easily acquiesce is on speeches and television commercials, where he often rewrites words that shape the core message of his candidacy.
During the research stage, we identified partner organisations based on their ability to deliver the core messages of the campaign.
The government made this one of the core messages of its "Are You Doing Your Bit?" campaign in 1999.
The core messages of the plan are an increase in self-reliance; reduced dependence on exports in general, and the US in particular; and greater environmental awareness.
The finding is one of the core messages of The Shakespeare Review, a government-commissioned report on what should happen next with opening up government data for the benefit of government, business and (of course) citizens.
The core messages of this directorate to the media are that Hamas broke the ceasefire agreements; that Israel's objective is the defence of its population; and that Israel's forces are taking the utmost care not to hurt innocent civilians.
