What is the 'causal body' and how is it related to achieving liberation or Moksha?

The causal body, also referred to as the 'Unmanifest' (Avyakruta), is described in Chapter 50 as being born from pure ignorance (Avidya) regarding the true nature of the Soul. It is the very cause of our perceived existence separate from the ultimate reality. The text explicitly states that the only way to remove this causal body and attain liberation, or Moksha, is through the knowledge of the unity of Brahman and the Soul. This realization dissolves the foundational ignorance, and the state of abiding in one's own true form is what is defined as Moksha.