Ideas have consequences.
The sin is not in conceiving forbidden ideas but in nursing and nourishing them. Consequences follow ideas. Once the demons of reckless practical atheism are loose in the house they poison the fountain of ideas in the imagination which feed ambition and behaviour. Shut in with himself, self-absorbed, narcissistic, sin deludes him with the easy assurance of immunity to divine interference. An atmosphere of isolation and unreality pervades his inner life.