In Book One of the Masnavi, Jalaluddin Rumi employs the metaphor of the letter or word as a container (zarf) and the spiritual meaning as water (ab), stating that 'the letter is a container, and meaning in it is like water' (harf zarf amad dar-o ma'ni cho ab). This directly builds upon Sanai's formulation in the Hadiqat al-Haqiqah, where the outward text of the Quran is treated as a vessel and its inner truth as water. Rumi uses this metaphor to argue that while verbal forms are necessary vehicles for communication, the seeker must transcend the physical words to access the infinite, divine ocean of meaning (bahr-e ma'ni).