Matsya Purana — The Terror of Tripura and the Gods’ Hymn to Śiva
भवतां च न पश्यामि कमप्यत्र सुरर्षभाः यस्तु चैकप्रहारेण पुरं हन्यात् सदानवम् //
bhavatāṃ ca na paśyāmi kamapyatra surarṣabhāḥ yastu caikaprahāreṇa puraṃ hanyāt sadānavam //
O foremost of the gods, I do not see anyone among you here who could, with a single blow, destroy that city together with its demons.
This verse is not about Pralaya; it highlights a crisis in the cosmic order where the gods lack the शक्ति (capacity) to destroy a demon-occupied fortress, setting up the need for an extraordinary intervention.
By analogy, it underscores a dharmic principle found across the Matsya Purana: when ordinary means fail against entrenched adharma, leadership must seek the most competent protector/agent rather than acting from pride or partial capability.
Architecturally, the key term is pura—an urban/fortified stronghold—used here as a symbol of an entrenched power-center; the verse itself does not prescribe Vastu rules but frames the fortress as an objective requiring decisive force.