Self is the only prison that can ever bind the soul.

The line frames spiritual confinement as self-made: the soul is not ultimately shackled by external circumstances but by the ego’s habits—fear, pride, resentment, and obsessive self-concern. In this view, “self” becomes a cell whose bars are internal narratives and attachments that narrow sympathy and freedom. The quote resonates with Van Dyke’s broader moral-religious sensibility (as a minister and essayist) that emphasizes character, humility, and service: liberation comes through self-forgetfulness, love, and a widening of attention beyond the ego. It also implies that genuine freedom is inward and ethical rather than merely political or material.