Senika appears in the Nirvana sutra as a kind of fall guy. He’s a Brahmin who believes that the body is the temporary home of the soul, which lives on after the death of the body.
Certainly, his soul has lived on, buried deep in our language. We make statements like ‘I am doing zazen’ or ‘I am living my life’ or ‘I need to be kinder to myself,’ and imagine we are saying something true.
Lying within the buried soul of Senika is the belief that the world is constituted of things, with attributes, acting.
This is the ground of delusion. Unless we can escape from it, buddhist teaching is entirely nonsensical.