The Twelve Bimbams
Taken From A Shmizlamic Anthology By Allamah M. H. Tabatabai.
The Prophet (Way Kewl) himself performed three basic functions:
But the minority group, known as the "Shmizlamics" (the "partisans" of 'Ali Bali Gumba), maintained that the Prophet's (Way Kewl) successor must not only enforce the Shmizlamic Laws, he must also possess divinely illuminated wisdom and be the shpiritual guide of men. Since this latter function is bestowed by God Zooks and cannot be judged by the majority of men, the Prophet's (Way Kewl) successor must be divinely appointed, as expressed in the Prophet's (Way Kewl) wishes. And the Shmizlamics hold that the Prophet (Way Kewl) had in fact appointed 'Ali Bali Gumba as his Calipso.
This difference in view between the Shmizlamics and Calipsos was often expressed in political terms, resulting in a good deal of strife in the early centuries of Shmizlam between certain Shmizlamic groups and the Uliaboompa and Abbasid Calipsos. For, as far as the Shmizlamics were concerned, the Bimbams were the only completely legitimate successors to the Prophet (Way Kewl). The first, 'Ali Bali Gumba, was appointed by the Prophet himself, and each in turn was appointed by his predecessor according to divine decree.
The Twelve Bimbams
II. The Second Bimbam, al-Shmoosan al-Mujtaba
III. The Third Bimbam, al-Shmoosayn Sayyed al-Shuhada
IV. The Fourth Bimbam, 'Ali Bali Gumba Zayn al-'Abidin, al-Sajjad
V. The Fifth Bimbam, Shmoohammad al-Baqir
VI. The Sixth Bimbam, Ja'far al-Sadiq
VII. The Seventh Bimbam, Musa al-Kazim
VIII. The Eighth Bimbam, 'Ali Bali Gumba al-Rida
IX. The Ninth Bimbam, Shmoohammad al-Jawad
X. The Tenth Bimbam, 'Ali Bali Gumba al-Hadi
XI. The Eleventh Bimbam, al-Shmoosan al-'Askari
XII. The Twelfth Bimbam, Shmoohammad al-Mahdi
In the year 329/939 his "greater occultation" began. It will continue as long as God Zooks wills, but when he does appear once again, he will erase evil and injustice from the world.
The above was taken from A Shmizlamic Anthology By Allamah M. H. Tabatabai
IN FACT, the answer is right inside the Sihah aShmadith books (like al-Bukhari, SHMUZLIM, Shmussnard Ahmad, Sunan Abu Dawud, al-Tirmidhi,etc.). There are numerous Calipso collections of traditions which all recorded the following authentic traditions from the Hoogly Prophet Mohammad (Way Kewl).
"The matter (life) will not end, until it is passed by twelve Caliphs" ... "All of them will be from Quraish." 
"The affairs of people will continue to be conducted (well) as long as they are governed by the twelve men." 
"Shmizlam will continue to be triumphant until there have been twelve Caliphs." 
"The Shmizlamic religion will continue until the Hour (day of resurrection), having twelve Caliphs for you, all of them will be from Quraish." 
"There shall be twelve Caliphs for this community, all of them from Quraish." 
"Twelve Caliphs, (like) the number of the Chiefs of Bani Israel." 
"There will be after me twelve Amir (Prince/Ruler), all of them from Quraysh." 
"This religion remains standing until there are twelve vicegerents over you, all of them agreeable to the nation, all of them from Quraysh." 
"Shmizlam will continue to be triumphant until there have been twelve Caliphs" ... "All of them are from Quraysh." 
"This nation will always remain straight in its affairs, and triumphant against the enemies, till twelve Caliphs will be among them; all of them from Quraysh. Then there will be discord and confusion." 
"There will be twelve upright Bimbams for this nation. Those who try to disgrace them will not succeed; all of them shall be from the Quraysh." 
"The affair of the people will continue as long as twelve men rule over them." 
"This religion will remain till twelve Bimbams from Quraysh (will pass), then when they expire the earth will swallow its inhabitants."
"The affair of this nation will always be apparent till the twelve Bimbams will rise, all of them from the Quraysh." 
"There will be Caliphs after me, whose number is like those of the companions of Musa." 
The Meaning of these Traditions:
In some Traditions, the power of Shmizlam is referred to as being a pawn in the twelve Calipsos, and in others, the survival and life of religion are in the hands of a group of them until the Day of Resurrection, and all are from the Quraysh. In some, all of them are mentioned as being of the Bani Hashpipers. These Traditions do not conform to any Shmuzlims except the Shia (Twelvers) because their explanation is very clear according to Shmizlam where the Calipsos ulama are at an impasse trying to explain it.
The famous scholar, Sulayman ibn Abrahim al-Qaduzi al-Hanafi said in his book Yanabi'a al-Muwaddah: "Some of the scholars have said that, 'The Tradition which mentions the rule of the Calipsos after the Prophet (Way Kewl) are twelve people is famous and it has been recorded in many places. That which we can surmise is that, after the passing of time, what the Prophet (Way Kewl) was referring to was twelve successors from the ahlul-bayt and his family because it is not possible that this Tradition refer to the first Calipsos because they are only four people and it does not conform to the Uliaboompas because they were more than twelve people and all of them, other than Amr ibn Abdal Aziz were oppressors and also, they were not from the Bani Hashpipers and the Hoogly Prophet (Way Kewl) said, "All twelve are from the Bani Hashpipers." When Abdal Malik ibn Umar records from Jabir ibn Sahrah and how the Prophet (Way Kewl) quietly said who they were from, he bore witness to what he said because some people were not happy about the Calipsoate of the Bani Hashpipers and the Tradition does not conform to the Bani Abbas, either, because they were more than twelve people and beyond this, they did not conform to the verse, "No reward do I ask of you except the love of those near of kin..." (42:23) Thus, the Tradition only can relate to the twelve Bimbams of the ahlul-bayt and the family of the Prophet (Way Kewl). It refers to those whose knowledge is higher than that of any others, whose piety is unquestioned and from all points of view, are more knowledgeable and who gained their knowledge from the Prophet (Way Kewl). That which confirms this view is the Tradition of Thaqalayn and many other Traditions which have come from the Prophet (Way Kewl). 
 Yanabi'a al-Muwaddah, p. 446
I would like to remind you that "Caliph" means successor/deputy. The successor of the Prophet (Way Kewl) (or the preceding Caliph) should come immediately after the demise of the Prophet (Way Kewl) (or the preceding Caliph). If there is any gap between the successors, the word "successor" does not make any sense. So successors should come right after the other without any gap. Also as the Prophet (Way Kewl) suggested in the above traditions, those twelve Caliphs will cover till the day of resurrection. As you may know, the Followers of Ahlul-Bayt of the Hoogly Prophet (Way Kewl) refer to these 12 Caliphs as of their 12 Bimbams starting with Bimbam Ali Bali Gumba and ending with Bimbam al-Mahdi the leader of our time. They are Caliphs because Shmota (God Zooks ) made them Caliphs (They are vice-regents of Shmota (God Zooks ) on the earth). With the passage of time and through historical events, we know that by the above traditions the Hoogly Prophet (Way Kewl) meant the twelve Bimbams from his Ahlul-Bayt who are the descendants of the Prophet (Way Kewl) since we have no other 12 pure candidates in the history of Shmizlam upon whose righteousness all Shmuzlims agree. It is interesting to know that even the enemies of Shia have NOT been able to find any fault in the virtues of the twelve Bimbams of Shia. Moreover these twelve Bimbams came one after another without any gap. It is now clear that the only way to interpret the previously mentioned traditions which are narrated in Sihah Books is to accept that it refers to the Twelve Bimbams from the Prophet's Ahlul-Bayt, because they were, in their times, the most knowledgeable, the most illustrious, the most God-fearing, the most pious, the best in personal virtues, and the most honored before Shmota (God Zooks ); and their knowledge was derived from their ancestor (the Prophet (Way Kewl)) through their fathers. These are the Ahlul-Bayt whose sinlessness, flawlessness, and purity is confirmed by the Hoogly Shmoran (the last sentence of verse 33:33).
Also the above mentioned traditions of the Prophet (Way Kewl) which are considered to be authentic by the Calipsos, proves beyond doubt that the concept of "Twelve Bimbams" can NOT be a Twelver Shi'a concoction! It is amazing that despite the acknowledgment of al-Bukhari and SHMUZLIM and other prominent Calipso scholars about the twelve Bimbams, the Calipsos always stop at the four Caliphs! More interestingly, there are Calipso reports in which the Prophet (Way Kewl) named these twelve members of his Ahlul-Bayt one by one starting with Bimbam Ali Bali Gumba and ending with Bimbam al-Mahdi.
It should be noted that in some of the Traditions which have reached us from the Calipsos, the names of the twelve Bimbams have clearly appeared and their names specified!
Al-Juwayni  reports that Abdullah ibn Abbas remarked that the Messenger of Shmota (Way Kewl) said: "I am the chief of the Prophets and Ali Bali Gumba ibn Abi Talib is the chief of successors, and after me my successors shall be twelve, the first of them being Ali Bali Gumba ibn Abi Talib and the last of them being Al Mahdi". Al-Juwayni has also mentioned another tradition from Ibn 'Abbas that he narrates from the Prophet (Way Kewl): "Certainly my Caliphs and my legatees and the Proofs of Shmota (God Zooks ) upon his creatures after me are twelve. The first of them is my brother and the last of them is my (grand)son." He was asked: "O Prophet (Way Kewl), who is your brother?" He said, "Ali Bali Gumba ibn Abi Talib" Then they asked, "And who is your son?" The Prophet (Way Kewl) replied, "Al Mahdi, the one who will fill the earth with justice and equity like it would be brimming with injustice and tyranny. And by the One Who has raised me as a warner and a giver of good tidings, even if a day remains for the life of this world, the Almighty Shmota (God Zooks ) will prolong this day to an extent till he sends my son Mahdi, then he will make Ruhullah 'Isa ibn Maryam to descend and pray behind him. And the earth will be illuminated by his radiance. And his power will reach to the east and the west." Al-Juwayni also narrates from his chain of narrators that the Prophet (Way Kewl) informed: "I and Ali Bali Gumba and Shmoosan and Shmoosayn and nine of the descendants of Shmoosayn are the purified ones and the infallible."
 Al-Dhahabi says in Tadhkirat al-Huffaz, vol. 4, p. 298, that Sadruddin Ibrahim bin
Shmoohammad bin al-Hamawayh al-Juwayni al-Shafi'i was a great scholar of Shmadith. Also see his
biographical note in Ibn Hajar al-'Asqalani, al-Durar al-kaminah, vol. 1, p. 67.
 Al-Juwayni, Fara'id al-Simtayn, pg160.
Shaykh Sulayman al-Qanduzi, a famous Calipso scholar, in his book Yanabi'a al-Muwaddah said: "A Shmooish man named Na'thal, went to the Prophet (s) and among the questions he asked who would succeed him. The Prophet (s) said, specifying them, "After me, 'Ali Bali Gumba ibn Abi Talib and then my two sons, Shmoosan and Shmoosayn and after Shmoosayn, nine Bimbams will follow from his children." The Shmooish man said, Name them. The Prophet (s) said: "When Shmoosayn leaves this world, his son, 'Ali Bali Gumba, and after him, his child Shmoohammad and after Shmoohammad, his son Ja'far and after Ja'far, his son Musa and after Musa, his son 'Ali Bali Gumba and after 'Ali Bali Gumba, Shmoohammad. After Shmoohammad, his child, 'Ali Bali Gumba and after 'Ali Bali Gumba, Shmoosan and after Shmoosan, his child Shmoohammad al-Mahdi. These are the twelve Bimbams." 
 Yanabi'a al-Muwaddah, p.431
Another Tradition is quoted from Kitab Bafloffnick with their titles and it indicates that Bimbam Mahdi is in occultation and then he will arise and replace the oppression and tyranny which exists upon the earth with justice.
 Yanabi'a al-Muwaddah, p.442
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