Shiva Purana
नावेदविद्भ्यः कथनीयमेतत्पुराणरत्नं पुरशासनस्य ॥ नाभक्तशिष्याय च नास्तिकेभ्यो दत्तं हि मोहान्निरयं ददाति ॥ ३८ ॥
This excellent gem of Śivapurāṇa should not be mentioned to those who do not know the Vedas, nor should it be imparted to a disciple who is not a devotee of Śiva nor to an atheist. If it is imparted to these out of delusion it yields hell.
english translation
nAvedavidbhyaH kathanIyametatpurANaratnaM purazAsanasya ॥ nAbhaktaziSyAya ca nAstikebhyo dattaM hi mohAnnirayaM dadAti ॥ 38 ॥
hk transliteration by Sanscript