• sandhyā-upagama — performance of the morning sandhyā worship
  The thrice-daily sandhyā (dawn, noon, dusk) is the brāhmaṇa's spinal practice. Bhagavān doing it Himself dignifies the rite as worship-of-Himself-by-Himself.
• huta-analaḥ — having offered into the sacred fire
  Fire-yajña is the Vedic householder's central act. Yet the BG (4.24, 9.16) reveals that all such offerings ultimately reach Kṛṣṇa, who is both yajña and yajña-bhuk. Here He performs the yajña He Himself receives.
• brahma — the Vedic mantra (Gāyatrī)
  Gāyatrī is called brahma because it is the mantra-mūla of the Vedas. That Bhagavān chants it 'silently' (jajāpa vāk-yataḥ) shows japa, not external recitation, as the gold standard — and the source-text for the whole Gauḍīya nāma-japa tradition.
• vāk-yataḥ — controlling speech
  Silence (mauna) during japa is the discipline Kṛṣṇa Himself models. Speech leaked outward dissipates the mantra; speech gathered inward feeds it. The whole rāgānuga-japa method rests on this.

Bhagavān bathing, dressing in cloth, and chanting Gāyatrī is the original of every brāhmaṇa's daily ritual — like the king who works the same plough as His farmers, not because He must, but because He wishes the plough to be honoured.