Matsya Purana — The Terror of Tripura and the Gods’ Hymn to Śiva
भयस्य यो वरो दत्तो मया मतिमतां वराः तस्यान्त एष सम्प्राप्तो यः पुरोक्तो मया सुराः //
bhayasya yo varo datto mayā matimatāṃ varāḥ tasyānta eṣa samprāpto yaḥ purokto mayā surāḥ //
O best of the wise, the boon concerning fear that I granted—its appointed conclusion has now arrived, O gods, exactly as I previously declared.
It emphasizes divine foreknowledge and control during Pralaya: the fear-related boon has a fixed term, and its end arrives exactly as foretold, showing cosmic events unfold according to declared divine order.
Indirectly, it teaches fidelity to one’s word and the certainty of results over time—key virtues for kings and householders in Purāṇic ethics (keeping promises, acting with steadiness when fear arises, and trusting righteous order).
No direct Vāstu or ritual procedure is stated; the takeaway is doctrinal: boons and vows have defined limits, a principle often echoed in ritual contexts where timings, durations, and stated intentions must be precisely observed.