Matsya Purana — Paurava Genealogy: Bharata
एवमुक्तः स गर्भेण कुपितः प्रत्युवाच ह यस्मात्त्वमीदृशे काले सर्वभूतेप्सिते सति अभिषेधसि तस्मात्त्वं तमो दीर्घं प्रवेक्ष्यसि //
evamuktaḥ sa garbheṇa kupitaḥ pratyuvāca ha yasmāttvamīdṛśe kāle sarvabhūtepsite sati abhiṣedhasi tasmāttvaṃ tamo dīrghaṃ pravekṣyasi //
Thus addressed, he—angered from within the womb—replied: “Since, at such a time, when what is desired by all beings is at hand, you obstruct it, therefore you shall enter long darkness.”
This verse is not about cosmic Pralaya; it uses “darkness” (tamas) as a moral-spiritual consequence, indicating a fall into ignorance/suffering due to wrongful obstruction.
It warns against unjustly prohibiting or blocking what is legitimately sought by beings—an ethical principle relevant to rulers (fair governance) and householders (non-harm, restraint from spiteful denial).
No Vastu or ritual procedure is specified in this verse; its focus is ethical causality (karma) expressed through the idiom of a curse leading to “long darkness.”