Materials: Oil on canvas. 

Symbolism: The Holy Cross. Crucifixion.

North: Chaos
The Ancient struggle before mankind. Law and order versus the uncontrolled forces of nature. Heaven and Hell.
West: Violence
The violence closely related to faith. Also a representation of Yang (male energy) and the Will to Power (Nietzsche).
Middle: Death
Dying Love. Also represents God is dead (Nietzsche).
East: Poetry
That what distinguishes us of the other primates. Also a symbol of Yin (female energy).
South: Innocence
Naivety. Religion has been reduced to windy skies and is diagnosed as mass psychosis. Reason awakes from the deep sleep. Peace can prevail. 

The painting:
North: Greek: Struggle of the Titans. Titans versus supreme God Zeus.
Christianity: Riders of the Apocalypse against God.
West: Achilles (utter left): Greek half God. The moment he has chosen for a peaceful existence as a musician, he is forced to reach to the arms. See the falling lyre (ancient musical instrument) and the sword. Perseus (with helmet): Greek half God. Warrior against evil. Son of supreme God Zeus & mortal Danaë, from immaculate conception. Comparable with God, Maria, Jesus.
Middle: Eros: Violence makes the Love God broken-winged. In the painting he crosses the river Styx to the realm of the dead. In the Greek myth an arrow of love penetrates his foot, which makes him in love with Psyche (female personification of the soul).
East: The Muses: Greek goddesses of singing, poetry, art and science. Victims of war. In her fall, one of the muses pulls the love arrow out of the foot of Eros. Aphrodite (utter right): Greek goddess of fertility, love and beauty. Finds her origin in eastern myths. Also regarded as the mother of Eros.
South: The Children. They only see figures in the clouds and let their imagination flow. Dogmatism is still strange to them.