Man is governed by his desires, lusts, that which pleases him. I God's presence. I can never take the first step in the Christian life until I see myself for who I am. A baby shares the nature of his parents. Lost person is decaying because of corrupt nature.
Saved person is alive because of divine nature within.
Nature determines environment - squirrels in trees, trout in water, moles in ground. Nature determines association - lion in prides, sheep in flocks, deer in herd. Behavior, env., assoc. We still have old flesh we struggle against. But our nature is God's.