I think you are right, Maggie!
I think it would be very easy to focus on the icon if it truly did have healing or supernatural powers instead of “divine God.” As humans I don’t think faith in religion is really our default setting, if you will. “Seeing is believing” is certainly a common outlook on life and I think most wouldn’t admit it, but witnessing something extraordinary in generally attributed to exactly what it appears to be; in the case of icons, divine icons and not necessarily divine God.