I'm looking for the part that talks about Saint Teresa's views on the 'wall' of separation from God. Is that in here?

The provided excerpts from the text do not mention Saint Teresa or her specific theological concepts. However, Chapter 19 does discuss a similar idea of a 'wall' in the context of the spiritual path. It states, "The sense of difference like 'I and Thou' is the wall between Guru and disciple; without tearing it down, the state of non-duality is certainly difficult to reach." This passage from Chapter 19 emphasizes that overcoming the sense of separation between oneself and the Guru is essential for spiritual progress. While it's not attributed to Saint Teresa, this concept of a 'wall' of duality is presented as a significant barrier that must be dismantled.