community soon became divided between the followers of Bah
'u'll
h (Bah
'
s) and those of his half-brother
ub
-i Azal (
Azal
s
). Turning over much of the task of organizing the movement to his eldest son and eventual successor, ‘Abb
s Effendi (
‘Abdu'l-Bah
), Bah
'u'll
h devoted his final years to his writings. These were now all regarded as revelations from God, and besides thousands of letters to his followers, included a number of lengthy books and ‘Tablets’ (
alw
). In his
Most Holy Book
(
c.
1873), he formulated the basis for a distinctive Bah