Page "Zohar" Paragraph 11

Believers in the authenticity of the Zohar countered that the lack of references to the work in Jewish literature were because bar Yohai did not commit his teachings to writing but transmitted them orally to his disciples over generations until finally the doctrines were embodied in the Zohar.

They found it unsurprising that bar Yochai should have foretold future happenings or made references to historical events of the post-Talmudic period.