Matsya Purana — Glory of Tīrtha-Śrāddha: Best Times
पितॄणां वल्लभं तद्वत् पुण्यं च विमलेश्वरम् पितृतीर्थं प्रयागं तु सर्वकामफलप्रदम् //
pitṝṇāṃ vallabhaṃ tadvat puṇyaṃ ca vimaleśvaram pitṛtīrthaṃ prayāgaṃ tu sarvakāmaphalapradam //
Likewise, beloved of the Pitṛs is the holy Vimaleśvara; and Prayāga—known as the Pitṛ-tīrtha—bestows the fruit of all desired aims.
This verse is not about Pralaya; it focuses on tīrtha-māhātmya—how certain sacred places (Vimaleśvara and Prayāga) are especially dear to the Pitṛs and confer spiritual merit.
It supports the householder duty of Pitṛ-yajña (honoring ancestors) through Śrāddha and related rites; visiting or performing offerings at a recognized Pitṛ-tīrtha like Prayāga is portrayed as highly efficacious for fulfilling obligations and lawful aspirations.
Ritually, it highlights Prayāga as a Pitṛ-tīrtha suited for ancestor-offerings and Vimaleśvara as a meritorious shrine; the emphasis is on correct pilgrimage and Śrāddha context rather than explicit Vāstu or temple-construction rules.