In closing the Third Stanza, Brahman is "Hansa Vahana" and Brahma is "Kala-Hansa." That is, Brahma is the vehicle of divine consciousness (the central point) on the ray from the immaculate white disk. "Narayan," who is Vishnu per G. de Purucker's Encyclopedic Theosophical Glossary, is therefore the 1st, 2nd, and 3rd Logos interchangeably (and thus equated with "Swayambhuva" or the self-evolving principle of the Kosmos) who penetrates the Mundane Egg to emerge as "Brahma or Prajapti" in the "future Universe." In this future Universe, Brahma is the "germ of unknown Darkness," and he becomes through self-expansion the "Universe woven out of his own substance."
In G. de Purucker's Studies on page 310, he outlined this upper triad according to Brahmanism. First, there is Parabrahman or Brahman. Second, there is Mulaprakriti or Pradhana. Third, there is Mahat. This Brahmanical structuring of the upper three logoi is followed in this commentary. The Mahat of this Primary Creation (above Alaya) is Brahma. Of course, there is a Secondary Creation where Mahat is below Alaya. So, we see that the upper three logoi of Parabrahman (the immaculate white disk), Mulaprakriti (the dull black ground), and Mahat (the central point) reflect themselves into the middle three logoi of Paramatman, Ad-Buddhi, and Mahat, per G. de Purucker's diagram in Fountain-Source on page 437.
With the Universe expanding, Svabhavat fulfills the role of Mulaprakriti (the 6th cosmical principle mirroring the 2nd Logos of Primary Creation). Mulaprakriti serves as the Space for the vibrating potential point and Svabhavat serves as the Space for the "universal vibration of atoms." In the same way that Fohat hardens the central point into the triplicate layers of cosmic suns (Central, Polar, and Equatorial) starting with the 7th cosmical principle, Fohat also "hardens the atoms" starting in the 4th cosmical principle and passes down into the life-force of Cosmic Jiva, Astral Light, and Sthula-Sarira.
Sources:
H.P. Blavatsky, The Secret Doctrine (Pasadena: Theosophical University Press, 2019).
G. de Purucker, Encyclopedic Theosophical Glossary. Retrieved from theosociety.org.
G. de Purucker, Fountain-Source of Occultism (Pasadena: Theosophical University Press, 1974).
G.de Purucker, Studies in Occult Philosophy (Pasadena: Theosophical University Press, 1973).

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