In Book 4 of the Masnavi, Jalaluddin Rumi utilizes the metaphor of butter (roghan) hidden within buttermilk (doogh) to illustrate the relationship between the eternal, divine spirit and the transient, material aspects of human existence. According to Rumi, the physical body and lower faculties (the animal spirit, partial intellect, illusion, and imagination) are visible and prominent like buttermilk, while the divine spirit remains invisible and seemingly non-existent within them, like butter dissolved in buttermilk. To separate and reveal the butter, the buttermilk must be churned in a vessel (khomreh). This churning represents spiritual discipline and the transformative guidance of a spiritual master or divine messenger, who shakes the seeker's material existence to awaken and manifest their true, hidden spiritual essence.