When not on the page, it's not that a word's meaning diminishes, it's that it has to share its essence with other artistic elements, starting with the painting itself; with the thing that has been made. Words on a page have been put there by the writer, the typesetter, the publisher, in a way that makes the words stand out alone, emphasizing them and putting them on the page to show them with the intent to best communicate meaning that the order of the letters dictate. That changes when words are used to paint. In painting, even the reason for language has a different purpose.
John Greiner-Ferris is an artist in the Boston area. Sometimes he makes images. Sometimes he writes. Sometimes he does both.