Matsya Purana — Manvantaras
शतार्धमङ्गुलानां तु ह्य् उत्सेधः शाखिनां परः मानुषस्य शरीरस्य संनिवेशस्तु यादृशः //
śatārdhamaṅgulānāṃ tu hy utsedhaḥ śākhināṃ paraḥ mānuṣasya śarīrasya saṃniveśastu yādṛśaḥ //
The supreme (standard) height of the limbs of an image is said to be one hundred and fifty aṅgulas; and the proportional arrangement of the human body is to be made accordingly.
This verse is not about Pralaya; it belongs to the technical iconography/measurement teaching, prescribing a standard height (in aṅgulas) and proportional body-arrangement for human-form representations.
It supports dharmic patronage: kings/householders commissioning temples and images should follow correct pramāṇa (measurement canons) so that worship is performed with properly proportioned icons, as taught in the Matsya Purana’s Vastuvidyā.
It gives an iconometric standard: the image’s overall height and limb-proportions are to be set by aṅgula-based measures, ensuring canonical proportions for mūrti-making and temple installation.