Tat started from Caduceus and Egyptian Sun Dials. The wings are the basics of good/evil on opposite sides. The Snakes come out of Egyptians as "The protectors of knowledge and the after life". You see the snake wrapped around the cross forming a double Helix (polar opposites, helix in DNA, everything happens in cycles) The wheel is a representation of the Event Horizon in space. This often also represents the passage of time. The cross represents my morals and values, or any religion.