Najul Israr

Moula Ali (as) said, " The first ibadat of Allah is marifat. The foundation of marifat is tawheed." (Ahtejaj Tabrisi ref Khutbat e Marifat e Allah Najul Israr First Edition pg. 156-157)

It is a common misconception amongst the Shia of today that all the
sermons and sayings ever given by Moula Ali (as) are all compiled
within Najul Balagha. Whenever Moula Ali (as) would give a sermon,
hundreds of poets, lecturers, scribes, etc. would write down the words
He spoke. So it is impossible for us to truly believe all of the
wonderful words of Moula (as) are contained in such a small book.
This is why our project team has set about translating the many other
sermons and sayings of Moula Ali (as) which are in various other
books. It is our goal to translate both editions of Najul Israr as these
two books contain a great many valuable sermons and sayings which
explain the true attributes of Masoomeen (as) as well as the true
beliefs of the Shia religion.