Matsya Purana — Inquiry into Taraka’s Slaying and the Prelude to Guha
दशवत्सरशेषस्य सहस्रस्य तदा दितिः उवाच शक्रं सुप्रीता वरदा तपसि स्थिता //
daśavatsaraśeṣasya sahasrasya tadā ditiḥ uvāca śakraṃ suprītā varadā tapasi sthitā //
Then Diti—abiding in austerity and empowered to grant boons—when ten years still remained of that thousand-year observance, spoke to Śakra (Indra) with great satisfaction.
This verse is not about Pralaya; it highlights the Puranic power of prolonged tapas (austerity) that culminates in boon-granting capacity and consequential divine dialogue.
Indirectly, it underscores the Matsya Purana’s ethic that disciplined vows and self-control over long periods produce spiritual authority—an ideal mirrored in royal and household discipline (vrata, restraint, and steadiness in duty).
No Vāstu or temple-architecture rule appears here; the ritual takeaway is the emphasis on sustained tapas/vrata over a fixed term (here, a thousand-year observance approaching completion).