In Book Five of the Masnavi, Rumi uses the historical narrative of Muhammad Khwarazmshah capturing the staunchly Shi'ite city of Sabzavar as a profound spiritual allegory. The king promises to spare the city's inhabitants only if they can present a man named 'Abu Bakr'—an impossible task in a purely Shi'ite population. Allegorically, the city of Sabzavar represents the corrupt, worldly human ego, while Khwarazmshah represents the divine presence or the spiritual master. The demand for an 'Abu Bakr' symbolizes God's strict requirement for a pure, sincere heart and genuine faith amidst a corrupted internal state. Rumi uses this to illustrate that mere worldly offerings or superficial pleas for mercy cannot substitute for true, foundational spiritual transformation.