The fox is a crafty and deceitful animal that never runs in a straight line, but only in circles. When it wants to catch birds to eat, the fox rolls in red mud so that it appears to be covered in blood. It then lies apparently lifeless; birds, deceived by the appearance of blood and thinking the fox to be dead, land on it and are immediately devoured.

The most famous fox of the Middle Ages was Reynard, the trickster hero of the Romance of Reynard the Fox.

The fox represents the devil, who pretends to be dead to those who retain their worldly ways, and only reveals himself when he has them in his jaws. To those with perfect faith, the devil is truly dead.

The most common fox illustration show the story of the fox luring birds by pretending to be dead. Several kinds of birds are shown descending on the "corpse" (magpies are common), often with one putting its head in the fox's mouth to get its tongue.