1. Fear of tyrannical Abbaside regime
When Abbaside rulers gained power they initiated the worst of atrocities and tortures on the Holy Imams (a.s). Basically they considered the school of Ahle Bayt (a.s) and anyone who was their adherents to be eligible for extreme pressure and restrictions. They were thrown into horrible prisons and then put to death. Poets and historians have drawn a pathetic picture of the perilous circumstances suffered by the Alawite Sayyids.
Abu Ataa says:
Alas! If only the oppression of the Merwanids (Bani Umayyah) had returned and the justice of Abbasides were destroyed and thrown into the fire.
Dibil Khuzai says:
The oppression of Bani Abbas has covered everything and no one was secure from its oppression. If we regard the oppression of Bani Umayyah an expected fact, as they were enemies of Bani Hashim, how can we justify the oppression of Bani Abbas who were themselves from Bani Hashima Yaqub bin Sikkit, an intellectual and a scholar of language says regarding Mutawakkil, the Abbaside, when he razed the tomb of the beloved one of the Holy Prophet (a.s) and harassed and tortured the visitors to his grave:
“It is true that Bani Umayyah unjustly killed the son of the daughter of the Prophet of Islam (a.s). But the Bani Abbas regretted not being present among them when they committed this crime. So their malice was expressed in mutilating the grave of the His Eminence…”
Abu Faras Hamadani has described the various kinds of tortures and atrocities wrought by the Abbasides with regard to Ahle Bayt (a.s) in the following words:
“The Abbasides have metamorphosed the religion of Allah and usurped the rights and subjected the progeny of Ali to humiliation and imprisoned and tortured them. Though the Bani Abbas can never reach the elevated position of the progeny of Ali (a.s). They cannot aspire for the exalted status of Bani Hashim. Their ancestor, indeed was not having even one-tenth of the position of the Progeny of the Prophet. Basically there is no similarity between the two clans. On the basis of this, the Progeny of Ali is great and honorable. Even though Abbasides are rulers, but in fact they shall remain servants of the Progeny of Ali (a.s).”
Abu Faras further satires the Abbasides thus:
“Why are these blatant behaviors and unsuitable things kept away from the Progeny of the Messengera Really, how deep you have gone into deceit in religion. How much blood of the Progeny of Messenger has been spilled at your hands! No matter how hard you try, you are going into further deviation. You can never gain the status of the Progeny of Ali. This is your Haroon who could not be compared with Musa bin Ja’far (a.s). And this is your Mamun, who like his father, was sunk in evil deeds and so he could not be compared to Ali bin Muse ar-Reza (a.s). The fact is that you exceed the Umayyads in your atrocities towards the progeny of the Prophet.”
Ibne Rumi has penned the following:
“You have two options before you. One is the straight path of truth and the other is a deviated road. Man is given the option to take one of the two. The path of enmity to the progeny of the Prophet, which is the path of deviation or the path of truth.”
Then he says:
“How prolonged is the path of usurping the rights of the Progeny of Ali (a.s) and their tortures and killings. How long would the progeny of the prophet be continued to be killed, and for how long would their blood continue to be spilleda How long would you continue to sell your religion to these rulers to whom you have paid allegiancea Is there none among you who could respect the rights of the Messenger of Allah (a.s) and have fear of the Lord of retributiona So that you may help them in such times of terrible calamities and oppressionsa”
He further says:
“Beware of the Bani Abbas and keep away from them. You should know that they are drowned in the sea of oppression and injustice. And their kingdom and regime is not permanent and it should not be a cause of your pride and deceit. Very soon an avenger shall arise and seek revenge of the blood of the progeny of the Messenger, which was spilled unjustly; because after every dark night there is a bright day.
Apparently, Ibne Rumi has alluded to the reappearance and advent of His Eminence, Imam Mahdi (a.s) who would rise up to establish his right.
The above were some examples of the atrocities the Abbasides had committed on the descendants of Imam Ali (a.s) that were versified by these poets.
source: The life of Imam al-Mahdi
by:Allama Baqir Sharif al-Qarashi