The text mentions a 'causal body.' What exactly is that, and how does one achieve liberation from it?

According to Chapter 50, the causal (karana) body of the soul is also known as the 'Unmanifest' (Avyakruta). It is described as the form that is with the reflection of consciousness and is the cause of pure ignorance. The text explains that the ignorance of the Soul is the cause of this body's existence. Liberation, or Moksha, is defined as the removal of this causal body, which can only be achieved through the knowledge of the unity of Brahman and the Soul. True Moksha is described simply as "abiding in one's own form," and there is no other path to liberation besides this realization.