You use the phrase ‘A Picture Paints a Thousand Words’ to indicate that a picture
or impression can express a complex idea in the same way a large amount of
descriptive text can.
Example of use: “Wow, this photograph really is amazing. A picture paints a thousand words!”
A similar expression to ‘A picture paints a thousand words’ first appeared in a 1911 newspaper article quoting editor Arthur Brisbane’s discussion of journalism and publicity: “Use a picture. It’s worth a thousand words.” During the discussion, Brisbane was making a clear-cut case for the use of images to accompany stories.