Ziyarat in the eyes of Imam al-Ridha (as)

Rayyan Ibn Shabib narrated:

Imam al-Ridha (as) said, “O Son of Shabib! Muharram is a month in which even the people of the former age of ignorance forbade oppression and bloodshed due to its sanctity. However, this nation did not honor the sanctity of this month nor did they honor the sanctity of their Prophet. In this month, they killed the Prophet’s progeny, enslaved his women, and plundered his belongings. May Allah never forgive them for these crimes.
O Son of Shabib! If you wish to cry for anything or anyone, cry for al-Husain Ibn Ali for he was slaughtered like a sheep. Eighteen members from his family who were unparalleled on earth were also killed along with him. Certainly, the seven heavens and earths cried because of the murder of al-Husain. Four thousand Angels descended on earth to aid him, but (when they were allowed to reach there) they found him martyred. So they remained at his grave, disheveled and dusty, and will remain there until the rising of al-Qa’im (Imam al-Mahdi), whereupon they will aid him. Their slogan will be, ‘Vengeance for the blood of al-Husain.’
O Son of Shabib! My father related to me from his father, who related from his grandfather that when my grandfather Imam al-Husain was martyred, the sky rained blood and red sands.
O Son of Shabib! When you weep over the afflictions of al-Husain so that tears flow from your eyes onto your cheeks Allah will forgive all your sins, big or small, few or numerous.
O Son of Shabib! If you wish to meet Allah, the mighty and the majestic, free of sin, then perform the Ziyarat of al-Husain.
O Son of Shabib! If it pleases you to abide in the palaces of Paradise in company of the Prophet and his family, then invoke Allah’s curse upon the murderers of Imam al-Husain.
O Son of Shabib! If you wish to earn the reward of those who were martyred with al-Husain, then whenever you remember him, say, ‘If only I had been with them so that I would have attained the great felicity.’
O Son of Shabib! If you desire to be with us in the highest degree of Paradise, then grieve in our sorrows and rejoice in our happiness. Remain attached to our love, for even if a person loves a stone, Allah shall resurrect him with it on the Day of Judgment.”

The Suffering of the Ahl ul Bayt (as) and their followers throughout history by Mateen J Charbonneau page 221-222