सूर्यरथनिर्णयः (चन्द्रस्य पक्षवृद्धिक्षयविधानम्)
पीत्वार्धमासं गच्छन्ति अमावास्यां सुरोत्तमाः पितरश्चोपतिष्ठन्ति अमावास्यां निशाकरम्
pītvārdhamāsaṃ gacchanti amāvāsyāṃ surottamāḥ pitaraścopatiṣṭhanti amāvāsyāṃ niśākaram
Pada hari Amāvāsyā (bulan baharu), para Dewa yang utama berangkat setelah ‘meminum’ selama setengah bulan; dan pada Amāvāsyā juga para Pitṛ mendekat serta berkhidmat kepada Bulan (Niśākara).
Suta Goswami (narrating the Linga Purana discourse to the sages of Naimisharanya)
It situates Amāvāsyā as a ritually potent junction where subtle beings (Devas and Pitṛs) are especially proximate, making offerings, purity, and Shiva-oriented observances (especially Pitṛ-related rites performed with Shaiva devotion) spiritually efficacious.
Indirectly, it highlights Shiva-tattva as the transcendent order (Pati) within which cosmic cycles—lunar phases, Deva movements, and Pitṛ access—operate; aligning one’s rites on Amāvāsyā supports the Pashu (soul) in loosening Pāśa (bondage) through dharmic and devotion-centered actions.
Amāvāsyā-focused Pitṛ-kārya such as tarpaṇa and śrāddha is implied; in a Shaiva frame, these are ideally performed with Shiva-smaraṇa and Linga-oriented worship to purify the practitioner and harmonize with the fortnightly (ardhamāsa) rhythm.