Some scholars believe that every ‘Rasool’ is necessarily a ‘Nabi’ as well; however a ‘Nabi’ may be or may not be a ‘Rasool’. Accordingly prophets are divided into two categories; those who are ‘Rasool’ and ‘Nabi’ combined; and those who are only ‘Nabis’. Another view is that ‘Rasool’ and ‘Nabi’ is one and the same thing. In the succeeding lines we will assess this viewpoint in the light of Quran.
When we look into Quran, we find very clear distinction between a ‘Rasool’ and a ‘Nabi’. Sura Hajj-52 states: “And We sent before you neither any ‘Rasool’ nor any ‘Nabi’ except that when he spoke …….”
In this verse, ‘Rasool’ and ‘Nabi’ have been clearly described as two different titles; by no means these two titles may be taken as one and the same thing. However these two different titles may be given to one person, but in no way these titles are essentially to be combined in a single person. It is possible that one person is given one title only and the other one is given the second one only. In other words, it is possible that one prophet may be a ‘Nabi’ only or a ‘Rasool’ only. However there may be prophets who are ‘Rasool’ as well as ‘Nabi’.
Keeping in line with above mentioned distinction, we find Quran has mentioned three categories of prophets; those who are ‘Nabi’ only; those who are ‘Rasool’ only; and those who are ‘Rasool’ and ‘Nabi’ combined.
Among those who are ‘Rasool’ and ‘Nabi’ combined include Hazrat Ibrahim; Hazrat Ismael; Hazrat Musa; Hazrat Isa and our prophet Muhammad (saw).
Among those who are ‘Rasool’ only include Hazrat Noah; Hazrat Lut; Hazrat Saleh; Hazrat Hud; Hazrat Shuaib; Hazrat yunus (as). These prophets have never been described as 'nabi' in Quran.
All the rest mentioned in Quran are ‘Nabis’. These prophets have never been described as 'rasool' in Quran.
It would be interesting to note that criteria of punishment is also different for non-believers of a ‘Nabi’ and non-believers of a ‘Rasool’.
Sura aaraf- 94,95 tell about criteria of punishment of non-believers of a ‘Nabi’; these verses state:
“And We sent to no city a ‘Nabi ‘[who was denied/ disobeyed] except that We seized its people with poverty and hardship that they might humble themselves [to Allah]. Then We exchanged in place of the bad [condition], good, until they increased [and prospered] and said, "Our fathers [also] were touched with hardship and ease." So We seized them (again) suddenly while they did not perceive”.
It is clear from these verses that disobedient/ non-believers of a ‘Nabi’ are not eliminated from the earth surface; though they are punished with poverty and hardships periodically, if they continue with their disobedience.
But non-believers/ disobedients of a ‘Rasool’ are eliminated completely. That is why we see that ummah of each of Hazrat Noah, Lut, Saleh, Hud, Shuaib (as) was eliminated, when the ummah opted disobedience to their respective ‘Rasool’; the ummah of Hazrat Yunus was forgiven only because of repentance.
Punishment criteria devised for non-believers/ disobedients of a ‘Nabi’ applies also to non-believers/ disobedients of a prophet who is ‘Rasool’ and ‘Nabi’ combined; the reason is that such prophet (as) is a Nabi as well apart from being a ‘Rasool’. Therefore we see that ummah of Hazrat Ibrahim (as); Hazrat Isa (as) [ both were Rasool-Nabi combined] were not eliminated though they disbelieved in their respective prophet.
Therefore we may conclude there are three types of prophets- Nabi only; Rasool only; and Rasool-Nabi combined. Quran has drawn clear distinctions between them. Regarding distinction of mode and medium of revelation given to these various types of prophets, my articles – ‘Wahi, Intuition and their Implications’; ‘Difference between Resalat and Nabuwwat’; and ‘Universality of Resalat, Ummah and Qadyaniat’ may be seen at the same blog.