सूर्यरथनिर्णयः (चन्द्रस्य पक्षवृद्धिक्षयविधानम्)
संभृतं त्वर्धमासेन ह्य् अमृतं सूर्यतेजसा पानार्थममृतं सोमं पौर्णमास्यामुपासते
saṃbhṛtaṃ tvardhamāsena hy amṛtaṃ sūryatejasā pānārthamamṛtaṃ somaṃ paurṇamāsyāmupāsate
अर्धमासेन संभृतं अमृतं सूर्यतेजसा। पानार्थं तद् अमृतं सोमं पौर्णमास्यामुपासते॥
Suta Goswami
It frames Soma (the Moon and Soma-substance) as amṛta gathered through cosmic law, making Paurṇamāsī a ritually potent time to offer and contemplate purity before worshiping Mahadeva as Pati, the giver of grace.
By pointing to amṛta sustained through the Sun–Moon order, it implies Shiva-tattva as the transcendent Pati who governs and sanctifies cosmic processes, turning worldly cycles into a means for the pashu to move beyond pasha.
Paurṇamāsī upāsanā of Soma—full-moon worship/observance—supporting vrata-like discipline and inner purification aligned with Shaiva practice.