Adhyaya 70: आदिसर्गः—महत्-अहङ्कार-तन्मात्रा-भूतसृष्टिः, ब्रह्माण्डावरणम्, प्रजासर्गः, त्रिमूर्ति-शैवाधिष्ठानम्
महान्सृष्टिं विकुरुते चोद्यमानः सिसृक्षया संकल्पो ऽध्यवसायश् च तस्य वृत्तिद्वयं स्मृतम्
mahānsṛṣṭiṃ vikurute codyamānaḥ sisṛkṣayā saṃkalpo 'dhyavasāyaś ca tasya vṛttidvayaṃ smṛtam
顕現しようとする意志に促され、彼は広大なる創造を展開する。その働きは二つと記憶される。すなわち、サンカルパ(saṅkalpa)という聖なる意図と、アディヤヴァサーヤ(adhyavasāya)という断固たる決定である。
Suta Goswami (narrating the Purana’s creation doctrine to the sages of Naimisharanya)
It frames creation as arising from Shiva’s inner power of intention and determination—supporting Linga worship as contemplation of the formless Pati whose will becomes the cosmos.
Shiva-tattva is presented as sovereign agency: the supreme Pati who, without external compulsion, manifests the great sṛṣṭi through saṅkalpa (intent) and adhyavasāya (unshakable resolve).
Saṅkalpa is directly implied: in Shiva-puja and Pashupata-oriented sadhana, the practitioner begins with a clear vow/intention and sustains it with firm adhyavasāya to loosen pasha (bondage) upon the pashu (soul).