Blame Umar [RA].
Three persons hated the most by the Majoosies, Umar [RA], Hazrat Aisha [RA], Abu Bakr [RA].
Allama Tamanna Imadi who wrote number of books, in one the book he says, the narrators used the trick of Mixing Honey with Poison. What he meant by that , They will narrate some good things about a sahaba, then some controversial matters linking that sahaba.
Allama Imadi was the person the great Thinker of the 20th century Allam Iqbal asked him to write a book debunking the theory of Nuzool Issa and Mehdi, while he was fighting the Qadiyani problem.[available at ebooks.rahnuma.org]
Hazrat Umar [RA], linking him with  bang,bang and bang-divorce.  Stoning to death. goat eating some pages of the Qur’an and  Taraweeh prayer. There may be several more.
 Qur.an details the step by step process of divorce.
 Punishment for adultery by lashing, not by stoning.
 Allah took the responsibility of protecting the Qur’an.
Their hatred for Umar [RA], is that during his rule the Battle of Qadsiya was fought, Rustum was killed on 10th of Muharram 14 AH.
[Ibne Jarir tabahi-volume 19-mentions two different date of Hazrat Hussain-27th of Safar and 10th of amauharram].
Uzair Ahmed Siddique –Sabai Sabz Bagh –page 26 Urdu –Translation in English below.
“ Shia follow the Muslim Judicial decree (Fatwa) of their alived Jurists, when the Jurist died his (Fatwa) also dissolved.
That is to say not to disclose the secret of their religion by referring the books of expired and Authors, therefore we will try to refer the books of alived Jurists and formed that, they have no religion nor faith, not respect Holy Prophet [AS]) nor any interest with Imam Ali and Ahle Bait, their religion just to use abusive language and false talking.
For the evidence of our claim, only one tract of Irani Poet is enough :
Beshikaste Omer Pusht Nabar Bran Ajam Ra
Barbad-o-Fana da Rag wa resha Ajam Ra
Ain Orbida bar ghasab Khilafat zali neest
Ba Ale Omer Keena Qadeem Ast Ajam ra
That is to say Omer (R.A) broken the waist of reputed/Personalities of Iran and damaged the dignity of offspring and Race of King Jamshed, our disputed with them not on this issue that why Ali was deprived from caliphate our objection only that Umer (R. A) and his offspring changed our ancient civilization and religion even our history and geography, hence by hanging the Chogha of Ahle Bait and concealed the hate of Islam in our breasts and the fire of impurity already cold in our fire temple, when its sparking still in our hearts, waiting only for concurrent to see how it is burst we were not allowed to adore the fire, hence we started adore the divine light of Ahle Bait, as and when our fire brusted, we will pour this divine light in fire temple and take the revenge from Islam.”
Another Translation in English
KURDI [a Persian poet ]in persian verses, has summed up the real feeling of the Majoosies. He says :-
"He (UMAR-Rd) broke the back of bravemen of AJAM, and destroyed the throne of
JAMSHEED, so our quarrel against him is not due to the usurpation of ALI's Khilafat but due to the old malice, AJAM bears against his family".
Ref. Religious –Tales or Fiction by Allama Habibur Rehman Kendhalvi –page 223