Batin (Islam)

Bāṭin () literally means "inner", "inward", "hidden", etc. The Quran, for instance, has a hidden meaning in contrast to its exterior or apparent meaning, the zahir. Sufis believe that every individual has a batin in the world of souls. It is the inward self of the individual; when cleansed with the light of one's spiritual guide, it elevates a person spiritually. 
This notion is connected to Allah's attribute of the Hidden One, who cannot be seen but exists in every realm.
Many Ismaili Muslim thinkers have stressed the importance of the balance between the exoteric ("zahir") and the esoteric ("batin") in the understanding of faith, and have explained that spiritual interpretation ("ta’wil") entails elucidating the esoteric meaning ("bātin") from the exoteric form ("zahir").
Muslim groups believe that "batin" can be fully understood only by a figure with esoteric knowledge. For Shia Muslims, that is the Imam of Time.
In a wider sense, it is the inner meaning or reality behind all existence, the "Zahir" being the world of form and the apparent meaning.
A grounding feature of Ismailism is the co-existence of the physical and the spiritual, the "zahir" (exoteric) form and the "batin" (esoteric) essence. The esoteric is the source of the exoteric, and the exoteric is the manifestation of the esoteric. This concept is highlighted in the “Epistle of the Right Path”, a Persian Ismaili prose text from the post-Mongol period of Ismaili history, by an anonymous author. 