Shiva Purana
राजसूयेन यत्पुण्यमग्निष्टोमशतेन च ॥ तत्पुण्यं लभते शंभोः कथाश्रवणमात्रतः ॥ २१ ॥
Merely by listening to the story of Śiva one derives the merit similar to that resulting from Rājasūya and a hundred Agniṣṭoma rites.
english translation
rAjasUyena yatpuNyamagniSTomazatena ca ॥ tatpuNyaM labhate zaMbhoH kathAzravaNamAtrataH ॥ 21 ॥
hk transliteration by Sanscript