Shiva Purana
एवं विंध्यतपो दृष्ट्वा प्रसन्नः पार्वतीपतिः ॥ स्वरूपं दर्शयामास दुर्ल्लभं योगिनामपि ॥ १४ ॥
On seeing the penance of Vindhya, Śiva, the delighted consort of Pārvatī, revealed to him his real form inaccessible even to the Yogins.
english translation
evaM viMdhyatapo dRSTvA prasannaH pArvatIpatiH ॥ svarUpaM darzayAmAsa durllabhaM yoginAmapi ॥ 14 ॥
hk transliteration by Sanscript