My first thoughts was in a nut shell, wow. This has got so much going on and I love it. The image was quite zoomed in at first so I noticed the soft lights and pastel colours in the background, only to find when i zoomed out the almost menacing outburst of the entire picture.
This was painted by Max Ernst, a German artist in the early 20th Century. His artwork was expressionist and strong. He first started his interest in philosophy and the art of the mentally ill, this bought his attention to the artist group known as "Rheinischen Expressionisten " meaning Rhenish Expressionists (artists of the Rhine, Rhineland, alongside Berlin, and the regions joining it).
The image is called "The temptation of St. Anthony" (oil on canvas).