Suwaid ibn Ghafalah reported that once he passed by a group of shee’ah who were talking about Abu Bakr and Umar in derogatory terms. Then he visited Ali ibn Abi Taalib and told him, “O Ameerul Mu’mineen, I passed by a group of your companions while they were referring to Abu Bakr and Umar in derogatory terms. If it were not that they thought that you secretly felt as they openly said, they would not have dared to say it” ‘Ali replied, “I seek refuge in Allah! I seek refuge in Allah from secretly feeling anything towards the two of them other than what the Prophet (sallallahu alayhi wasallam) entrusted to me. May Allah curse anyone who holds inside himself anything but goodness and gratitude towards both of them. (they were like) two brothers to Allah’s Messenger (sallallahu alayhi wasallam), his two companions, his two assistants, may Allah’s mercy be on both of them”.
Then Ali got up with tear in his eyes, holding onto my hand until he entered the masjid. Next he ascended the mimbar and sat at its top holding onto his beard and looking at it until people gathered. After having made a brief but eloquent speech, he added “What is wrong with those who make allegations about the two masters of Quraysh, the two fathers of the Muslims, allegations which I would never say or ever want to hear others say; and for which I may be punished. By he who split the seed and created the soul, only a pious believer loves them, and only a wretched sinner hates them. Those two who accompanied Allah’s Messenger, commanding all that is good and prohibiting all that is evil; who became angry with wrongdoers and punished them based on truth and honesty alone. In their rulings, they did not overstep the opinions of Allah’s Messenger. In fact, their opinions always coincided with those of Allah’s messenger and the believers were pleased with both of them throughout their respective caliphates.
The Messenger of Allah (sallallahu alayhi wasallam) appointed Abu Bakr to lead the believers in their prayers for the last nine days of the prophet’s life and he died without recalling him. The believers, subsequently, made him responsible for their affairs, and gave him their Zakaah. They willingly pledged allegiance to him and I am the first from Banu Abd al mutallib to confirm his leadership. He disliked leadership and wished that one of us would take his place. By Allah, he was the best of those who remained after the prophet (sallallahu alayhi wasallam); the eldest, the kindest, and truly the most compassionate and pious. He was like angel Mikaeel in his benevolence and prophet Ibraheen in his willingness to forgive and his dignified bearing. He took the path of the Prophet and passed away on that path (may Allah be pleased with him).
After Abu Bakr, Umar took command, and I was among those pleased with his appointment. He ruled according to the policy of Allah’s Messenger and his companion, Abu Bakr, following their footsteps the way the young camel follows its mother. I swear by Allah, he was kind and gentle with the weak, a champion of the cause of the oppressed and without any blame concerning Allah’s religion. Allah manifested examples of the truth through him and made the truth a part of him to such a degree that we used to think that an angel was speaking with his tongue. Allah made his conversion a strengthening factor for islaam, and placed in the hearts of the hypocrites a fear of him and in the hearts of the believers love for him. Allah’s Messenger (sallallahu alayhi wasallam) compared him to angel Jibreel to his harshness towards the enemies of islaam. So who among you can be compared to the two of them?! May Allah’s mercy be on them, and may Allah provide us with the ability to continue in their paths. Let whoever loves me, love them, for whoever does not love them has angered me, and I will have nothing to do with him. If I hear anymore derogatory talk about the two of them, I will punish the offenders severely. After today, whoever is brought before me will get the punishment of a slanderer. Verily the best of this nation after its Prophet is Abu Bakr and Umar, may Allah be pleased with them. Then Allah knows who is the best, I am saying this asking Allah’s forgiveness for both you and myself.”
Taken from Talbis Iblis of Ibn Al-Jawzi