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Shiavault - a Vault of Shia Islamic Books Your Questions Answered (volume 5) Q. 20: How Many Ulul''azm? How many ulul- 'azm Messengers were there? A. We know of five. They were Nuh (Noah), Ibrahim (Abraham), Musa (Moses), 'isa (Jesus) and Muhammad. Only the shari'ah brought by Muhammad (which is generally known as Islam) is valid now; it has abrogated all the previous shari'ah.
Q21: THE RELATION BETWEEN NABII (PROPHET) AND RASUL (MESSENGER) "The dictum 'Every Messenger was a Prophet', deserves this comment: The Prophet (Nabii) is a helping class, and the messenger (Rasul) is a class that is helped. "And when Allah made a covenan 'with the prophets: Certainly what I have given you of Books and Wisdom - then a messenger comes to you verifying that which is with you, you must believe in him and you must aid him." (Qur'an, 3:81).
Moreover, the messengers (Rasuls) need help even in the Akhirat: "Most surely we help our messengers and those who believe, in this world's life and on the day when the witnesses shall stand up." (40:51). A. First of all, the verse 3:81 refers to the covenant taken from all the prophets about the Holy Prophet of Islam - that they would believe in him and help him by giving his good news to their nations and telling them to believe in him when he comes along.
This Is generally agreed explanation found both in Sunni and Shi'a books and traditions. Second: Even this verse shows that the prophets were required to "believe in" and help the messenger. Evidently it shows the higher status of the messengers. Third: Prophets and messengers were not two mutually exclusive classes. According to general Islamic belief, based on prophetic traditions, there were 124,000 prophets- out of which 313 or 300 were messengers (among whom, 5 were ulul-'azm).
Thus, every messenger was a prophet but not every prophet was a messenger. Fourth: Your observation that prophets were a helper class and messengers the helped ones, is amusing. Do you mean to say that they were two mutually exclusive groups? Then what will you say about those messengers who have been called "messenger prophet"? Were they the helpers or the helped ones? Vide Qur'an, 7:157, 7:158, 19:51, 19:54, etc.
You say that the messengers (Rasuls) need help even in the Akhirat, and quote this verse: "We will without doubt help our messengers and those who believe, in this world's life and on the day when the witnesses shall stand up." (40:51).