Can you summarize the main purpose of a saint's advent as explained in Chapter 4 of the Sai Satcharitra?

The central theme of Chapter 4 is explaining why saints take an incarnation on Earth. The text posits that they descend when religion is in decay and people have lost their moral and spiritual compass. Their purpose is multi-faceted: to protect the system of castes and stages of life, to destroy irreligion, and to protect the poor and weak. As Chapter 4 clarifies, saints come to reawaken faith and guide humanity back to the ultimate goal (Paramartha) when people are lost in worldly pursuits. Their work is a selfless act of compassion, aimed at uplifting the distressed and restoring righteousness.