Based on Chapter 4, what is the fundamental purpose of a saint's incarnation in a world where people have lost their way?

Chapter 4 explains that the fundamental purpose of a saint's incarnation is to restore dharma and guide humanity back to the path of ultimate well-being (Paramartha). When people lose their way, becoming obsessed with lust, hunger, and worldly attachments like wealth and family, they miss the chance for self-upliftment. As described in Chapter 4, saints descend to this mortal world to counter this decay. Their purpose is to protect the system of castes and stages of life, destroy irreligion, and awaken faith, thereby building a foundation of renunciation upon which the temple of Ultimate Truth can be constructed for the benefit of all devotees.