Ayat al-Tathir Analyzing Tathir Verse from A New Perspective This book has been written by Grand Ayatollah Fazel Lankarani and late Ayatollah Shaikh Shahab al-Deen al-Ishraqi, Imam Khomeini's son-in-law (may peace be with them). The book's original language was Persian but later it was translated into Arabic. It is explicitly stated in this book that Ayat al-Tathir was exclusively revealed about Ahlalbayt (a.s.) i.e. the Kisa (cloak) members not anyone else.