Matsya Purana — The Battle at Tripura: Shiva’s Strategy
तं नन्दिभुजनिर्मुक्तं मुक्ताफलविभूषितम् पपात वक्षसि तदा वज्रं दैत्यस्य भीषणम् //
taṃ nandibhujanirmuktaṃ muktāphalavibhūṣitam papāta vakṣasi tadā vajraṃ daityasya bhīṣaṇam //
Then that terrible vajra—released from Nandī’s arm and adorned with strings of pearls—fell upon the demon’s chest.
This verse does not address pralaya; it focuses on a mythic combat moment where a fearsome vajra strikes a demon, emphasizing divine intervention and the inevitability of adharma’s defeat.
Indirectly, it reinforces the Purāṇic ethic that destructive force is justified only when directed against adharma—an ideal echoed in rājadharma where punishment (daṇḍa) must be decisive yet righteous.
No Vāstu or temple-building rule is stated here; the main ritual-symbolic takeaway is the vajra as a consecrated emblem of irresistible power used for restoring cosmic order.