بسم الله الواحد القهار
And among what has been narrated is that which our Sheikh, the Jurist, Abul Hasan Ibn Shadhaan narrated to us, he said: narrated to me my father, may Allah bless his soul, who said: narrated to us Ibn Al-Walid, Mohammad Ibn Al-Hasan, saying: narrated to us Al-Saffaar from Mohammad Ibn Al-Husain who said: narrated to us Mohammad Ibn Ziyad from Al-Mufaddal Ibn Umar from Yunus Ibn Ya'qub, may Allah be pleased with him, who said: I heard As-Sadiq, Ja'far Ibn Mohammad(عليهما السلام) saying: "Cursed is a body, cursed is the body that is not afflicted in every forty days."
So I said: "cursed?" He said: "yes, cursed", so when he saw that it was difficult for me to accept, he said: "O Yunus, among the afflictions could be also a scar, a thrust, a mistake, a misfortune and poverty, being away from home and so on. O Yunus, a believer is honored by Allah more than that to leave him forty days and does not clean his sins, even by afflicting him with a little sadness, that he might not even know where that sadness comes from and even some of you might receive some money but thinks that some of it is missing, so he becomes sad, but later he finds out that nothing was missing, and that would wash away some of his sins. O Yunus, cursed is a person, cursed is he who harms his neighbor, cursed is a person, cursed is he who when his brother offers him a compromise/peace he does not accept it, cursed is a person, cursed is he who is a reciter of Qur'an yet insists on drinking alcohol, cursed is a person, cursed is he who is a scholar yet serves a tyrannt ruler, assisting him in his oppression, cursed is a person, cursed is he who is a hater of Ali Ibn Abi Talib(عليه السلام), because he can't hate him unless he hates the Messenger of Allah(صلی الله وعليه وآله) and whoever hates the Messenger of Allah(صلی الله وعليه وآله), Allah curses him in this world and hereafter. Cursed is a person, cursed is he who accuses a believer of being a disbeliever, and if a person accuses a believer of disbelief it is as if he has murdered him. Cursed is a woman, cursed is she who angers her husband and makes him sad, and blessed is a woman, blessed is she who respects her husband and does not anger him and obeys him in all his affairs.
O Yunus, my grandfather the Messenger of Allah(صلی الله وعليه وآله) said: 'Cursed is the person, cursed is he who oppresses my daughter Fatima(سلام الله عليها) after me and usurps her right and murders her.' He then said: 'O Fatima, glad tidings for you, for there is a high rank for you in front of Allah, you will intercede with that position for those who love you and for your Shia and Allah will accept your intercession. O Fatima, if every Prophet(عليهم السلام) that Allah has sent and every Angel that Allah has given a high rank intercede for every person who hates you, who has usurped your right, Allah will never take him out of the Hellfire.'
Cursed is a person, cursed is he who cuts his kin relations, cursed is a person, cursed is he who confirms sorcery, cursed is a person, cursed is he who says that Imaan is just proclaiming it without doing good deeds, cursed is a person, cursed is he whom Allah has given wealth, but he refuses to give charity. Have you not heard that the Prophet(صلی الله وعليه وآله) said: 'Giving one dirham alms is superior to ten nights of prayers'? Cursed is a person, cursed is he who beats his father or mother. Cursed is a person, cursed is he who has been disinherited/disclaimed by his parents, cursed is a person, cursed is he who does not respect the mosque. O Yunus, do you know that Allah has given mosques a high honor and has revealed this verse: 'And the mosques are only for Allah, so pray not unto anyone along with Allah[72:18]', the jews and the christians used to consider others as gods beside Allah, so Allah, the Exalted, ordered his Prophet(صلی الله وعليه وآله) to believe only in one God and worship Him only."
Source: Kanzul Fawahid, Vol. 1 Pg. 149-151
Grading: Sahih(authentic).
For more information read the response of Sayyed Sadiq Ar-Rohani below.
Sayyed Sadiq Ar-Rohani:
598: About the oppressors of Az-Zahra(سلام الله عليها)?
Question: Al-Karajaki has narrated in his book Kanzul Fawahid, Vol. 1 Pg. 149-150 from Abul Hasan Ibn Shadhaan from his father from Mohammad Ibn Al-Hasan Ibn Al-Walid from Mohammad Ibn Al-Husain Al-Saffaar from Mohammad Ibn Ziyad from Mufaddal Ibn Umar from Yunus Ibn Ya'qub from As-Sadiq(عليه السلام) who said in a long narration: "O Yunus, my grandfather the Messenger of Allah(صلی الله وعليه وآله) said: 'Cursed is the person, cursed is he who oppresses my daughter Fatima(سلام الله عليها) after me and usurps her right and murders her.'"
Is the chain of this narration authentic?
Response: There is nothing wrong with the authenticity of its chain, because Al-Mufaddhal Ibn Umar has been considered trustworthy by Sheikh Al-Mufid in his book Al-Irshaad and he has praised him and Al-Kashi has narrated many narrations in his praise that indicates his high status and deputyship, and trustworthiness, as the author of Al-Wasahil mentions and there is no need to mention the sources in detail about this issue, you should refer to sources like Bihar and what the opponents have narrated through reliable chains with clear content that are not hidden from even the blind one, let alone those who can see.
Source: Alf Fatwa Wa Suhal Fi At-Taqlid Wal Aqaed, Pg. 323.