What does Chapter 23 say is the root cause of human suffering and the only way to escape it?

According to the teachings in Chapter 23, the human soul is, in reality, Existence-Consciousness-Bliss (Sacchidananda) but becomes deluded by Maya, causing it to forget its true nature and identify with the body. This leads to pride and the false belief of being the "doer" and "enjoyer," which in turn results in a succession of calamities. The text clearly states that the only way to calm these calamities and find escape is through loving devotion (Bhakti Yoga) at the feet of the Guru.