Can anyone explain to me what is going on in this 1710 painting by Dutch master Aert De Gelder?

Here is some information about the UFO in this picture http://www.uforc.com/religion/AF_moviesUFO-content...

Also, quote at http://www.funtrivia.com/askft/Question99226.html:

It certainly looks like what is now called a UFO, but similar things appear in other paintings. For example in Carlo Crivelli's 1496 painting of The Annunciation - now in London's National Gallery of London - the angel Gabriel appears as a "UFO" launching a ray on the face of the Virgin. However, strange things have been seen in the sky for centuries and were often considered to be divine manifestations. None of the artists were eyewitnesses of Biblical events and so they probably were following an artistic convention of the time.

It appears to be a sample of traditionally arranged typography. Personally my eye is drawn first to "404 error page not found," but this is open to interpretation.