Shiva Purana

siva.sh/siva-purana/saturda-samhita/8/25

ऋग्वेद उवाच।। यदन्तस्स्थानि भूतानि यतस्सर्व्वम्प्रवर्त्तते।। यदाहुः परमन्तत्त्वं स रुद्रस्त्वेक एव हि ।। २५ ।।

sanskrit

Ṛgveda said:— That in which the Bhūtas stay, that from which everything comes out, what they call as the greatest entity—that is Rudra alone.

english translation

Rgveda uvAca|| yadantassthAni bhUtAni yatassarvvampravarttate|| yadAhuH paramantattvaM sa rudrastveka eva hi || 25 ||

hk transliteration by Sanscript