Matsya Purana — Origin of Soma
तथेत्युक्तः स आजह्रे राजसूयं तु विष्णुना होतात्रिर् भृगुरध्वर्युर् उद्गाताभूच्चतुर्मुखः //
tathetyuktaḥ sa ājahre rājasūyaṃ tu viṣṇunā hotātrir bhṛguradhvaryur udgātābhūccaturmukhaḥ //
Thus instructed, he arranged the Rājasūya, the royal consecration-sacrifice, for Viṣṇu: Atri served as the Hotṛ priest, Bhṛgu as the Adhvaryu, and the Four-faced One (Brahmā) became the Udgātṛ.
This verse does not discuss pralaya; it focuses on a royal Vedic ritual (Rājasūya) and the appointment of officiating priests for a sacrifice connected with Viṣṇu.
It reflects rajadharma: a ruler’s duty to uphold cosmic and social order through properly conducted śrauta rites, appointing qualified ṛṣis as priests and honoring Viṣṇu through sanctioned royal consecration rituals.
Ritually, it specifies the śrauta structure of a major yajña by naming the core priestly functions—Hotṛ, Adhvaryu, and Udgātṛ—underscoring that correct personnel and Vedic roles are essential to the Rājasūya’s validity.