INTRODUCTION
As he have seen before, the politics of his times were so bad that Imam (A.S) could not openly preach Islam. If he did so, his enemies would get a chance of preventing him from doing so by putting him away in prison or even killing him.
He could not therefore all the time preach as openly as his grandparents had done before him.
As an Imam appointed by Allah, he knew when to openly expose the enemies of Islam and when to preach Islam without openly naming the enemies.
Whenever possible, he gave sermons in which he openly named the enemies of Islam and the wrongs that they did to the family of the Prophet, though such moments were rare. Otherwise, the Imam used the supplications (Duas) and sayings to teach proper Islam as opposed to Islam which was being preached by the oppressive government of Bani Umayyah.
Source:
A Brief Biography of Ali Ibn Husain (a.s)
By: Muhammad Reza Dungersi. PH.D
[Vol. 1, Pg. 31].
