Matsya Purana — The Origin of Yajña in Tretā Yuga and the Debate on Animal Sacrifice vs. Non-...
अन्तर्हितायां संध्यायां सार्धं कृतयुगेन हि कालाख्यायां प्रवृत्तायां प्राप्ते त्रेतायुगे तदा //
antarhitāyāṃ saṃdhyāyāṃ sārdhaṃ kṛtayugena hi kālākhyāyāṃ pravṛttāyāṃ prāpte tretāyuge tadā //
When the twilight-junction (saṃdhyā) had disappeared along with the Kṛta Yuga, and the phase called “Kāla” had begun to operate, then the Tretā Yuga was attained.
It does not describe Pralaya directly; it sets the cosmic-time framework by marking the end of Kṛta Yuga (and its junction) and the commencement of a ‘Kāla’ phase leading into Tretā—background chronology often used in Purāṇas to situate later events.
Indirectly: by indicating entry into Tretā Yuga—an age in which ritual order, rule-bound dharma, and regulated social duties become more pronounced compared to Kṛta—this chronology supports later prescriptions for kingship, sacrifice, and household discipline.
No explicit Vastu/temple rule appears in this verse, but yuga-transition markers commonly function as ritual-historical anchors in the Matsya Purana, clarifying when specific sacrificial norms and formal procedures (more emphasized in Tretā) become applicable.