Shiva Purana
विना मंत्रेण हो धत्ते रुद्रा क्षं भुवि मानवः । स याति नरकं घोरं यावदिन्द्रा श्चतुर्दश ८३ ।
The man who wears the Rudrākṣa without mantra falls into a terrible hell and stays there during the tenure of fourteen Indras.
english translation
vinA maMtreNa ho dhatte rudrA kSaM bhuvi mAnavaH । sa yAti narakaM ghoraM yAvadindrA zcaturdaza 83 ।
hk transliteration by Sanscript