I, 3, 35

35. And because the kṣattriyahood (of Jānaśruti) is understood from the inferential mark (supplied by his being mentioned) later on with Caitraratha (who was a kṣattriya himself).

Jānaśruti cannot have been a Śūdra by birth for that reason also that his being a kṣattriya is understood from an inferential sign, viz. his being mentioned together (in one chapter) with the kṣattriya Caitraratha Abhipratārin. For, later on, i.e. in the passage complementary to the saṃvarga-vidyā, a kṣattriya Caitrarathi Abhipratārin is glorified, 'Once while Śaunaka Kāpeya and Abhipratārin Kākṣaseni were being waited on at their meal a religious student begged of them' (Ch. Up. IV, 3, 5). That this Abhipratārin was a Caitrarathi (i.e. a descendant of Citraratha) we have to infer from his connexion with a Kāpeya. For we know (from Śruti) about the connexion of Citraratha himself with the Kāpeyas ('the Kāpeyas made Citraratha perform that sacrifice;' Tāṇḍya. Br. XX, 12, 5), and as a rule sacrificers of one and the same family employ officiating priests of one and the same family. Moreover, as we understand from Scripture ('from him a Caitrarathi descended who was a prince^[1]') that he (Caitraratha) was a prince, we must understand him to have been a kṣattriya. The fact now of Jānaśruti being praised in the same vidyā with the kṣattriya Abhipratārin intimates that the former also was a kṣattriya. For as a rule equals are mentioned together with equals. That Jānaśruti was a kṣattriya we moreover conclude from his sending his door-keeper and from other similar signs of power (mentioned in the text).--Hence the Śūdras are not qualified (for the knowledge of Brahman).