Śatapatha Brāhmaṇa ("of a hundred paths") 6.1.3.20

6.1.3.20

tametaṃ saṃvatsara eva cinuyāt | saṃvatsare 'nubrūyāddūyorityu haika āhuḥ saṃvatsare vai tadreto 'siñcantsa saṃvatsare kumāro 'jāyata tasmāddūyoreva cinuyādvūyoranubrūyāditi saṃvatsare tveva cinuyātsaṃvatsare 'nubrūyādyadvāva retaḥ siktaṃ tadeva jāyate tattato vikriyamāṇameva vardhamānaṃ śete tasmātsaṃvatsara eva cinuyātsaṃvatsare 'nubrūyāttasya citasya nāma karoti pāpmānamevāsya tadapahanti citranāmānaṃ karoti citro 'sīti sarvāṇi hi citrāṇyagniḥ

One ought to build him (Agni, the fire-altar) up in (the space of) a year, and recite for a year. 'For two (years),' however, say some; 'for in one year they laid the seed, and in one year that boy was born, therefore let him build for two (years), and recite for two (years).' Let him, however, build for a year only, and recite for a year; for the same seed which is laid is brought forth; it then lies changing and growing: hence let him build for a year only, and recite for a year. To him (Agni) when built up (kita) he gives a name: whereby he keeps away evil from him. He calls him by a bright (kitra) name, saying, 'Thou art bright;' for Agni is all bright things.