Śatapatha Brāhmaṇa ("of a hundred paths") 13.4.4.1

13.4.4.1

saṃvatsare paryavete dīkṣā prājāpatyamālabhyotsīdantīṣṭayaḥ purohitasyāgniṣu yajetetyu haika āhuḥ kimu dīkṣito yajeta dvādaśa dīkṣā dvādaśopasadastisraḥ sutyāstattriṇavamabhisampadyate vajro vai triṇavaḥ kṣatramaśvaḥ kṣatraṃ rājanyo vajreṇa khalu vai kṣatraṃ spṛtaṃ tadvajreṇaiva kṣatraṃ spṛṇoti

When the year has expired, the Dîkshâ (initiation) takes place. After the slaughtering of the victim sacred to Pragâpati, the (ishti) offerings come to an end. Some, however, say, ‘Let him offer (them) on the fires of his Purohita (court-chaplain). But why should one who is initiated make offering? There are twelve Dîkshâ (days), twelve Upasad (days) and three Sutyâs (Soma-days), that amounts to the thrice-ninefold (stoma); but the thrice-ninefold, indeed, is a thunderbolt, and the horse is the nobility (kshatra), and the Râganya is the nobility; and political power (kshatra) is won by the thunderbolt: thus he wins political power by means of the thunderbolt.