Shiva Purana
ये चापवादं कुर्वंति विमूढाश्शिवयोगिनाम् ॥ श्रोतृभिस्ते प्रपद्यन्ते नरकेष्वामहीक्षयात् ॥ ३८ ॥
Those who disparage Śivayogins under delusion undergo sufferings in hells along with those who listen, till the dissolution of the world.
english translation
ye cApavAdaM kurvaMti vimUDhAzzivayoginAm ॥ zrotRbhiste prapadyante narakeSvAmahIkSayAt ॥ 38 ॥
hk transliteration by Sanscript