Kauṣītaki (Śāṅkhāyana) Brāhmaṇa 5.1.21

5.1.21

tan nakṣatriyām virājam āpnoti / (Cāturmāsya)

The full moon night is the Phalgunīs in the beginning of the year; the latter two Phalgus are the beginning, the two former the end. Just as the two ends of what is round may unite, so these two ends of the year are connected. In that he sacrifices with the Vaiçvadeva sacrifice on the full moon night in the Phalgunīs, verily thus at the beginning he delights the year. Again the four-monthly sacrifices are sacrifices of healing; therefore are they performed in the joinings of the seasons, for in the joinings of the seasons pain is born. There are eight oblations, the oblations of four full moon days amount to eight; the Vaiçvadeva is a compound of four full moon days. In that Agni is kindled, it is because the Vaiçvadeva is propagation; therefore he generates this divine embryo. As to there being seventeen kindling verses, the butter portions containing the word 'being', the invitatory and offering verses being Virāj verses, the explanation of that has been given. In that there are nine fore-offerings and nine after-offerings, eight oblations and the offering for the steeds as the ninth, thus he obtains the brilliance of the Nakṣatras.