In the year 21 A.H., some people of Kufah came to Hazrat ‘Umar رضي الله عنه and laid complaints against Hazrat Sa’d رضي الله عنه who was their governor. Hazrat ‘Umar رضي الله عنه thus dismissed him (from his position as governor, in order to quell the fitnah that the people were attempting to create), and appointed Hazrat ‘Ammaar bin Yaasir رضي الله عنه in his place.
When these people of Kufah complained about Hazrat Sa’d رضي الله عنه, they even complained that he was not performing salaah correctly! Hazrat ‘Umar (radhiyallahu ‘anhu) thus called for Hazrat Sa’d رضي الله عنه. When he arrived, Hazrat ‘Umar رضي الله عنه addressed him with the utmost respect saying, “O Abu Ishaaq (this was the kunyah (filial title) of Hazrat Sa’d رضي الله عنه)! Indeed, these people are claiming that you do not perform salaah correctly.
Hazrat Sa’d رضي الله عنه replied, “By Allah! As for myself, then I would perform for them the salaah which Rasulullah صلى الله عليه وسلم had taught us, without any deficiency.” Hazrat Sa’d رضي الله عنه then gave an example of how he emulated the salaah of Rasulullah صلى الله عليه وسلم mentioning, “When I lead them in the ‘Esha Salaah, I lengthen the first two rakaats and shorten the second two rakaats.” Hazrat ‘Umar رضي الله عنه replied, “O Abu Ishaaq! That is the exact opinion that I held regarding yourself!”
Hazrat ‘Umar رضي الله عنه thereafter sent Hazrat Sa’d رضي الله عنه back to Kufah with a few people (in order to investigate the allegations against Hazrat Sa’d رضي الله عنه, so that his innocence may be proven and his name cleared). They thus went to every musjid of Kufah and asked the people regarding Hazrat Sa’d رضي الله عنه. When questioned, the people had nothing but praise for Hazrat Sa’d رضي الله عنه.
Finally, they reached a musjid in the district of the Banu ‘Abs tribe. Here a man named Usaamah bin Qataadah, whose kunyah was Abu Sa’dah, stood and said, “Since you have asked me, then Hazrat Sa’d رضي الله عنه does not go out in Jihaad with the army, he does not distribute wealth with equality, and he is not just in his verdicts and decisions.”
Hearing these false allegations, Hazrat Sa’d رضي الله عنه replied, “By Allah! I will make three du‘aas – O Allah! If this servant of yours is lying, and he has merely stood for fame and recognition, then lengthen his life, extend his poverty, and involve him in fitnah.”
Thereafter, if Usaamah bin Qataadah was asked how he was, he would reply, “I am very old and I am entangled in fitnah. The curse of Hazrat Sa’d رضي الله عنه afflicted me.”
One of the narrators of this incident, ‘Abdul Malik, mentions, “I saw him (Usaamah bin Qataadah) afterwards. His eyebrows were drooping over his eyes due to old age, and he was interfering with the young slave girls by prodding and poking them in the street.”
(Saheeh Bukhaari #755)
Note:
We see from the above narration that Usaamah bin Qataadah had laid false allegations against Hazrat Sa’d رضي الله عنه and disgraced him before the people. However, Hazrat Sa’d رضي الله عنه did not curse him unconditionally. Rather, he exercised caution and justice when cursing him. When cursing him, he suspended the curse on the person being worthy of it, asking Allah to only afflict him if he was deliberately lying.
Usaamah bin Qataadah laid three allegations against Hazrat Sa’d رضي الله عنه. The first pertained to his personal self by accusing him of cowardice, and so Hazrat Sa’d رضي الله عنه cursed him with a long life. The second accusation was regarding wealth, and so Hazrat Sa’d رضي الله عنه cursed him with poverty. The third accusation was an accusation pertaining to Deen, as he said that Hazrat Sa’d رضي الله عنه did not perform Salaah correctly, and so Hazrat Sa’d رضي الله عنه cursed him in Deen by making du‘aa that he become entangled in fitnah.
The above explanations have been taken from Fat-hul Baari 2/276-281.
Hazrat ‘Umar رضي الله عنه knew that Hazrat Sa’d رضي الله عنه was innocent. However, to close the doors of fitnah, he replaced Hazrat Sa’d رضي الله عنه with Hazrat ‘Ammaar bin Yaasir رضي الله عنه. Imaam Maalik رحمه الله has mentioned, “Hazrat ‘Umar رضي الله عنه dismissed Hazrat Sa’d رضي الله عنه whereas he was the most just of all the governors who would come after him until Qiyaamah.” Fat-hul Baari 2/281
Hence, shortly before passing away, Hazrat ‘Umar رضي الله عنه formed a Shura (council) of six Sahaabah رضي الله عنهم who were worthy of the khilaafah after him. These six Sahaabah رضي الله عنهم were Hazrat ‘Uthmaan رضي الله عنه, Hazrat ‘Ali رضي الله عنه, Hazrat Talhah رضي الله عنه, Hazrat Zubair رضي الله عنه, Hazrat Sa’d رضي الله عنه and Hazrat ‘Abdur Rahmaan bin ‘Auf رضي الله عنه. Hazrat ‘Umar رضي الله عنه had explained that he selected these six Sahaabah رضي الله عنهم as Rasulullah صلى الله عليه وسلم was most pleased with them at the time of his demise.
Hazrat ‘Umar رضي الله عنه mentioned that these six Sahaabah رضي الله عنهم should decide among themselves as to who would be the Khalifah. He had also included his respected son, Hazrat ‘Abdullah bin ‘Umar رضي الله عنهما, in the Shura, and gave instructions that he would not be appointed as Khalifah, but would assist them in nominating the Khalifah.
At the time of including Hazrat Sa’d رضي الله عنه in the Shura, Hazrat ‘Umar رضي الله عنه declared the innocence of Hazrat Sa’d رضي الله عنه saying, “The person who they appoint will be the Khalifah after me, even if Hazrat Sa’d رضي الله عنه is appointed. If Hazrat Sa’d رضي الله عنه is not appointed as Khalifah, then the Khalifah after me should ensure that he seeks assistance from Hazrat Sa’d رضي الله عنه, as I did not dismiss him from the governorship of Kufah due to any shortcoming or betrayal on his part.” Siyar A’laam min Nubalaa 3/74
(Whatisislam.co.za)

