Hannity doesn't *know* God created the Universe any more than anyone else does. He *believes* it, just like you and other believers do. That is the most anyone can say, if they are honest about it.
If you want to be picky about it, nobody “knows” anything. Those people you call(ed) your parents - you don’t remember your birth therefore you could have been lied to all these years. Is George Washington really a founding father of this country or is your life really A Truman Show and we fed you baloney. Did the War of 1812 really exist? Can you prove it? Photos? Pieces of paper? Really, can you prove anything?