He had been on a mission in Isfahan and Mashhad where he successfully defended the views of his master, Siyyid Kazim, before the leading clerics of those cities. Upon reaching Karbala, Mulla Husayn became aware of the death of his master, Siyyid Kazim. Being told that Siyyid Kazim had left them no Will, Mulla Husayn asked the other students about the last words of their departed master. They told him that Siyyid Kazim had bidden them repeatedly and emphatically to quit their homes, scatter far and wide, purge their hearts from every idle desire, and dedicate themselves to the search for Him to Whose advent Siyyid Kazim had so often alluded.
After a period of mourning and 40 days of prayer and fasting in the vicinity of the shrine in Najaf he sets out for Persia in the company of his brother and his nephew, following last wishes of Siyyid Kazim that his followers quit Karbala and search for the Promised One. The party go to Bushihr and then on to Shiraz. (Adaped from 'A Basic Baha’i Chronology', by Glenn Cameron and 'Mulla Husayn Disciple at Dawn', by R. Mehrabkhani)