These four Khulafaa (pl. for Caliph) are called the "Khulafaa-e-Rashidun" or the "Rightly Guided Caliphs." Together, these four Khulafaa ruled the Islamic State for about 29 years. They are called "Rightly Guided"because they ruled the people of that time exactly according to the Holy Quran and the commands of Sayyiduna Rasulullah (sallal laahu alaihi wasallam).
 

Quotation

"Those who are desirous of following anyone, should follow the Sahaba who were the best of community, whose hearts were pure, whose wisdom was profound and who did not believe in the exhibition of outer life. They were a people whom Allah had selected His Nabi (sallal laahu alaihi wasallam) and who extended His religion to the world. Therefore, try to imitate their ways and manners, for by Allah, they were rightly guided people."
 

A Hadith on the Status of the Four Khulafa

Once I visited the Holy City of Mecca and met a man who claimed that he never felt thirsty. When I asked him the reason for this strange event, he replied, "There was a time when I did not have any respect for the Sahaba of Muhammad (sallal laahu alaihi wasallam). One night, I dreamt that it was the Day of Qiyamah and there were many people in various queues looking very thirsty and ragged. I decided to follow a queue. We arrived at the Fountain of Kauther and saw that it had four corners. At each corner were the four Caliphs, Sayyiduna Abu Bakr, Sayyiduna Umar, Sayyiduna Uthman and Sayyiduna Ali (radi Allahu anhum). I thought that there was no need for me to approach the first three Caliphs as I only believed in Sayyiduna Ali (radi Allahu anhu). Yet, when I approached him, he turned his head away in displeasure. Feeling extremely alarmed, I approached the other three Caliphs and they also behaved in the same manner. By now I was very despondent.

"I noticed that Nabi Muhammad (sallal laahu alaihi wasallam) was also approaching the Fountain. I ran towards him and explained to him the behaviour of the four Caliphs. He replied, 'Why should beloved Ali offer you a cool drink, when you bear hatred and scorn for the Sahaba?' When I heard this, I asked Sayyiduna Rasoolullah (sallal laahu alaihi wasallam) whether I would be forgiven or not if I asked pardon for my incorrect beliefs. He replied that I would be forgiven. I then recited the Kalimah again and asked for forgiveness. I was then ordered to return to the Fountain of Kauther and drink from it. After this, I awoke from my sleep. From that night onwards, I have never felt thirsty. I then warned my family that I would only accept those as my true family if they accepted my true beliefs. Some of them did accept".

The presence of the four Caliphs at the four Pillars of Kauther is also substantiated by a Hadith. Sayyiduna Rasoolullah (sallal laahu alaihi wasallam) said, "The Fountain of Kauther possesses four Pillars: one commanded by Abu Bakr, the second by Umar, the third by Uthman and the fourth by Ali (radi Allahu anhum)".

Again, explaining the lofty status of these four Caliphs, Sayyiduna Rasoolullah (sallal laahu alaihi wasallam) said, "He who speaks good about Abu Bakr, his religion is well established; he who speaks good about Umar, his religious path has been well grounded' he who speaks good about Uthman is enlightened with the Noor of Almighty Allah' and he who speaks good about Ali holds on to a bond that never breaks. They who speak well of my Sahaba (Companions) are truly Mu'mins". (Shawaa'idul Haqq)