As the page explains: [...] the artist was in fact 67 years old when he painted this picture in 1651.
(snip)The youthful artist's face, by contrast, shows Bailly as he was at an earlier stage in his life, more than four decades previously. Thus, by changing the time references of past fiction and present reality, the painting suggests that the young artist is anticipating his future age, which - though part of the present in 1651 - appears to belong to the past, as conveyed through the medium of the portrait. The young man, who appears to be so real within the first-degree reality of the painting, really represents a state of the past.
Also from the WGA is this depiction (anonymous) of St Luke painting the Virgin which is best described as 'cute'.