Its evidence is also present in Holy Rigved, Mandal 10, Sukta 90, and Mantra 16.
It is also evident in RigVed Mandal 9 Sukta 96 Mantra 17 to 20,
that the Supreme God KavirDev(Kabir Parmeshwar) appears by acquiring the form of a child and delivers His pure knowledge i.e. Tatvgyan to His followers through(KavirgirbhiH) Kabir Vaani by telling aloud.
It is also evident in RigVed Mandal 9 Sukta 96 Mantra 17 to 20,
that the Supreme God KavirDev(Kabir Parmeshwar) appears by acquiring the form of a child and delivers His pure knowledge i.e. Tattavgyan to His followers through(KavirgirbhiH) Kabir Vaani by telling aloud.
An alternate explanation is that the word'Shudra' does not occur anywhere else in the Rig-veda except the Purusha Sukta,
leading some scholars to believe the Purusha Sukta was a composition of the later Rig-vedic period itself to denote,
legitimise and sanctify an oppressive and exploitative class structure that had already come into existence then.