How would you write a one-liner law against theism?

[rado84]

Say you're a statesman of the highest order in a country, where you can basically write any kind of law without needing them to pass any kind of legislation whatsoever. Ignoring how foreign countries might view the matter, what kind of law or rule would you make against theism or religions? I'll go at it first  

"Distribution of any theistic ideas without prior implication and explicit acknowledgement of their falsehood is illegal and punishable by law."

Theists don't care about the laws of men but they're more afraid of being sinners, so: "Worshipping any deities is a mortal sin". That should do.