व्यपोहनस्तवनिरूपण-प्रसङ्गे नक्तभोजन-शिवव्रतविधिः (वार्षिक-प्रतिमास-क्रमः)
पक्षयोरुपवासं च चतुर्दश्यष्टमीषु च
pakṣayorupavāsaṃ ca caturdaśyaṣṭamīṣu ca
亦当于月之两半行持斋戒(upavāsa),尤以第十四日(caturdaśī)与第八日(aṣṭamī)为要——此等修持净化缚魂(paśu),令其心志安定,趋向主宰帕提(Pati)、湿婆大自在。
Suta Goswami (narrating Shiva-dharma and vrata-vidhi to the sages of Naimisharanya)
It prescribes upavāsa (fasting) on sacred tithis—especially caturdaśī and aṣṭamī—as a core preparatory discipline that supports purity, restraint, and focused devotion before Linga-pūjā.
By directing the practitioner toward regular austerity, it implies Śiva as Pati—the transcendent Lord approached through inner purification, where the paśu becomes fit to receive grace (anugraha) by loosening pāśa (bondage).
Upavāsa as vrata/niyama: a Shaiva observance aligned with Pāśupata discipline, using lunar tithis (aṣṭamī, caturdaśī) to stabilize mind and senses for worship and japa.