Bhashya
अथ येऽस्योदञ्चो रश्मय इत्यादि समानम् ।अथर्वा-ङ्गिरस अथर्वणा अङ्गिरसा च दृष्टा मन्त्रा अथर्वाङ्गिरस ,कर्मणि प्रयुक्ता मधुकृत ।इतिहासपुराण पुष्पम् ।तयोश्चे-तिहासपुराणयोरश्वमेधे पारिप्लवासु रात्रिषु कर्माङ्गत्वेन विनि-योग सिद्ध ।मधु एतदादित्यस्य परं कृष्ण रूपम् अतिशयेनकृष्णमित्यर्थ ॥
In plain words
Now, the passage beginning with 'the northern rays of this sun' is explained similarly. The Atharvāṅgirasas are mantras envisioned by the sages Atharva and Aṅgiras, functioning as bees in sacrificial rites. History and mythology serve as the flower. Furthermore, the employment of history and mythology as part of the ritual during the Pāriplava nights of the horse sacrifice is well established. This honey is the supreme dark form of the sun—meaning it is intensely dark.
Close to the Sanskrit
Now, those rays of this [sun] which are northward and so on is the same. The Atharvāṅgirasas are mantras perceived by Atharva and Aṅgiras, employed in rituals as honey-makers. History and mythology are the flower. And the practical application of both history and mythology as a subsidiary ritual part during the Pāriplava nights in the horse sacrifice is established. Honey: this is the supreme dark form of the sun, meaning it is exceedingly dark.