Enmity

Pronunciation:
\ˈen-mə-tē\

Definition:
positive, active, and typically mutual hatred or ill will

Etymology:
Middle English enmite, from Anglo-French enemité, enemisté, from enemi enemy

First Known Use: 13th century

Excellent word! This word came up today in Sunday School:
 
Romans 8:7-8 (KJV)
Because the carnal mind is enmity against God: for it is not subject to the law of God, neither indeed can be. So then they that are in the flesh cannot please God.
 
Basically, The Message:
Focusing on the self is the opposite of focusing on God. Anyone completely absorbed in self ignores God, ends up thinking more about self than God. That person ignores who God is and what he is doing. And God isn't pleased at being ignored.

Not just natural enemies, but enemies who are actively living out their hatred for one another.