Vacaspatya 4.15.14

4.15.14

bhāgīrathī godāvaryādikā nadyeva kālaḥ kutaścidutpattisthānādutpadyate | taccotpattisthānaṃ sāṃkhyoktaṃ prakṛttiḥ
triguṇabhoktrātmā vā śrutyuktyuditā nityakālātmaka
īśvaro vā bhaviṣyati | yathā tāṃ gaṅgādikāṃ mahānadī
manyāṃ khalnanadyo'bhitaḥ praviśanti sā ca praviṣṭairnadyantaraiḥ
saha vistīrṇā pravahatpravāhā satī na kadācit śuṣyati
evaṃ nānāvidharūpaiḥ samutpannāḥ kālabhedāḥ saṃvatsarākhyaṃ
pradhānaṃ kālamāśritāḥ | tatra nimeṣādyā ayanaparyyantāḥ
kālabhedāḥ saṃvatsarāṭṇavo, yugādyāḥ parārddhaparyyantāḥ saṃvatsarānmahāstaste sarvve taṃ saṃvatsaraṃ samyak praviśanti | aṇā
nāmaṇayāttvena praveśaḥ | mahataḥttu saṃvatsarādyattiniṣyādyānāmadhyakṣaḥ saṃvatsaraiti tatra praveśo'bhidhīyate | tathāca
vedaṅgajyotiṣamanthe paṭhyate "pañcasaṃvatsaramayaṃ yugādhyakṣaṃ
prajāpatim | dinarvvayanamāsāṅgaṃ praṇamya śirasā sthita
iti | saca saṃvatsarastairabhibhedairusa sarvai samāviṣṭo'tidīrghaḥ sarvvāṇi jagaṃti na chidyāta iti | nanvaṇu tya
nimeṣe paryavasitaṃ mahttvaṃ tu parārddhe tathā ca tayoranyatarasya prādhānyamacitam | tat kathaṃ saṃvatsarasya prādhānyam
iti cet īśvareṇa prathamaṃ sṛṣṭatvāditi brūmaḥ | tathā
ca vājasaneyinaḥ samāmananti "so'kāmayata dvitīyoma
ātmājāyeteti sa manasā vācā niśūnaṃ samabhavadāttadeta
vāsīt sa saṃvatsaro'bhavaditi" | tammātsaṃvatsaraḥ pradhānam, ataeva vayaṃ saṃvatsaramārabhya kālaviśeṣaṃ nirṇīyāmaḥ
tatra saṃvatsaro'yanaṛturmmāsaḥ pakṣaḥ tithirnakṣatraṃ yoga
ityevaṃ vidhāḥ karmāṅgānāḥ | yadyapi purāṇeṣu vyamārkaṇḍe -