IMAM HUSSAIN-the true Imam

Punishment for the one who addresses Yazid as "Radhiallahu Anhu"

The Just Caliph of the Clan of Ummayyah, Hadhrat ‘Umar bin Abdul ‘Aziz (May Allah be well pleased with him) declared the person who addressed Yazid as "Radhiallahu Anhu" as liable to be punished.

This is written in "Tahdheeb Ut Tahdheeb", the authoritative book on Rijal (the science of the classification of men, for the purpose of categorizing the Hadith), by Imam Ibn Hajar ‘Asqalani, in Vol. 11, the Arabic letter "Ya", Pg No. 316.  Imam Ibn Hajar Haitami has written in "As Sawaiiq Al Muhriqa" on Pg No. 132 and Imam Jalaluddin Suyuti (May Allah shower His mercy on him) in Tarikh Ul Khulafa Pg No. 166.

Translation:  Noufal bin Abu Aqrab states:  I was in the presence of Hadhrat ‘Umar bin ‘Abdul ‘Aziz (May Allah shower His mercy on him) when one person while talking about Yazid said: Amir Ul Momineen Yazid said so and so and Amir Ul Momineen said so and so  Hadhrat Umar bin Abdul ‘Aziz (May Allah shower His mercy on him) said:  You address Yazid as ‘Amir Ul Momineen’ and ordered that he should be lashed 20 times.  Hence, he was lashed 20 times.

Imam Badruddin ‘Aini (May Allah shower His mercy on him) writes in the interpretation of the Hadith

My Ummah will be destroyed at the hands of a few lads of Quraish:

Translation: Yazid was the first among those lads, and wrote along with Yazid’s name: "On him is what he deserves."