Matsya Purana — Characteristics of Dvāpara and Kali Yugas
उपहत्य तथान्योन्यं साधयन्ति तदा प्रजाः दुःखप्रचुरताल्पायुर् देशोत्सादः सरोगता //
upahatya tathānyonyaṃ sādhayanti tadā prajāḥ duḥkhapracuratālpāyur deśotsādaḥ sarogatā //
Then the people, injuring one another, pursue their own ends; sorrow becomes abundant, lifespans grow short, the land falls into ruin, and disease becomes widespread.
It is not a cosmic pralaya verse; it describes moral and social “decline” (dharma-ksaya) where violence, disease, and reduced lifespan afflict a region—an inner-world deterioration rather than universal dissolution.
By portraying mutual harm and widespread suffering as marks of decline, it implies the king’s duty to restrain violence, protect subjects, and uphold dharma, while householders should avoid exploitation and cultivate non-injury and social responsibility.
No direct Vastu or ritual rule is stated; the practical takeaway is contextual—when a land is “ruined” and “diseased,” purification, public welfare measures, and dharmic governance become urgent prerequisites for stable settlement and temple/ritual life.