In Book One, Section 124 of the Masnavi, Rumi provides an esoteric interpretation of the Quranic verse 'He released the two seas meeting; between them is a barrier they do not transgress' (Surah Ar-Rahman, 55:19-20).

He metaphorically equates the 'two seas' to the 'people of light' (heavenly souls) and the 'people of fire' (hellish souls). While both groups physically co-exist and mingle in the material world, they remain fundamentally distinct in their spiritual essence. An invisible divine barrier (barzakh) preserves their separation, illustrating the continuous interplay and underlying distinction between good and evil, peace and conflict, in the human realm.