The scholars of Ahl al-Sunnah wa al-Jamâ`ah have concurred on the view that the four Rightly Guided Caliphs are ranked in honor according to their order of succession to the post of Caliph. The best of them was the first caliph, Abû Bakr, then `Umar, then `Uthmân, then `Alî.
There is a large body of evidence to support this belief.
Ibn `Umar said: “In the time of the Prophet (peace be upon him) we used to give preference to Abû Bakr, then to `Umar, then to `Uthman.” [Sahîh al-Bukhârî (3655)]
Even though this is the statement of a Companion, it takes the ruling of a statement of the Prophet (peace be upon him), since it is quoting what the people used to say during the Prophet’s lifetime without the Prophet (peace be upon him) having voiced any objection to it.
It is directly stated in other narrations that the Prophet (peace be upon him) heard this being said and had no objection to it. [Sunnah Ibn Abî `Asim (1227) and Sunnah al-Khalîl (577)]
There is also evidence that the Companions – and they were quite a substantial number – raised no objection to this order of preference. [Musnad Ahmad (4626)]
Muhammad b. al-Hanafiyyah, the son of the fourth Caliph `Alî b. Abî Tâlib, said: “I asked my father: ‘Who was the best person was after Allah’s Messenger (peace be upon him)?’ He replied that it was Abû Bakr. I asked: ‘Then who?’ He replied with `Umar. I was afraid that he would mention `Uthman next, so I asked him: ‘Then you?’ So he said: ‘I am but a man from among the Muslims’.” [Sahîh al-Bukhârî (3671)]
Ibn Mas`ûd relates: “We assembled together as the companions of Muhammad (peace be upon him) and we did not pass over the best among us without exception – so we gave pledged our allegiance to the Commander of the Faithful `Uthmân.” [Musnad Ahmad (391,731, and 759) with an authentic line of transmission]
This is a clear case of the Companions arriving at a unanimous agreement that the best of them after ``Umar was `Uthmân.
These texts are clear in their indication of a preference between these Caliphs according to the order in which they served as Caliph. This is especially true since one of these texts is a direct profession of this preference from the fourth of them, `Alî b. `Abî Tâlib.
As for `Alî being the fourth in rank from among the Companions, it is indicated by his being the fourth Caliph and by all of the hadîth that extol his virtues and his distinctions to a degree not even remotely shared by any of the other Companions aside from the other three Rightly Guided Caliphs, as we have already discussed.
Source: Islam Today