These are the core doctrines innovated by the Yemeni Jew, Abdullah bin Saba', as found in what has been preserved about him in the narrations, and much of which is also acknowledged in the Shia sources, (many of which are listed in this article):

1. Al-Wasiyyah: The Legacy. He is the first who spoke of the alleged wasiyyah (legacy) of the Messenger (sallallaahu alayhi wasallam) for Ali (radiallaahu anhu) in that he (Ali) is to be the khalifah after him for the Ummah.

2. He spread hatred and enmity against the likes of Abu Bakr, Umar the rest of the companions (radiallaahu anhum) and disavowed himself from them.

3. He was the first to claim the Uluhiyyah and Rububiyyah (Lordship) for Alee (radiallaahu anhu) and spread ghuluww (exaggeration) with respect to the Ahl al-Bayt.

4. He was the first to claim Prophethood amongst the extremist Shia sects, this is mentioned by al-Kashi (d. 370H) in his book al-Rijaal (a Shia source).

5. Al-Raj'ah: The Return. He was the first to claim the return of Ali (radiallaahu anhu) after his death, and likewise the return of the Messenger of Allaah (sallallaahu alayhi wasallam) after his death. He spread this in Egypt, and he used to say, "How strange is the one who claims Eesaa will return and rejects the return of Muhammad, yet Allaah, the Mighty and Majestic says, "Verily, He Who has given you (O Muhammad) the Qur'an will surely bring you back to the place of return" (28:85), so Muhammad is more worthy of rerturn than Eesaa." So the people accepted this from him and so he invented the doctrine of the return and the people began to speak about it thereafter.

6. He claimed that Ali (radiallaahu anhu) is the (دابة الأرض) mentioned in the Qur'an, and that he is the one who created the creation and gives sustenance.

7. A group from the followers of Ibn Saba' (Sab'iyyah) said that they do not die in reality but their souls "fly" in the darkness of night after their death, and so they were called the "Tayyaarah".

8. A group from the Sab'iyyah also spoke of the "Ruh al-Qudus (Holy Spirit)" being transmitted through their leaders. They claimed that it was in the Prophet (sallallaahu alayhi wasallam) just as it was in Eesaa, and then it went to Ali, then to Hasan, then to Husayn (radiallaahu anhum) and then through to all their Imaams. This faction therefore believed in the transmigration of souls (tanaasukh al-arwaah), and some of the early Shia authors wrote to refute this idea, such as al-Naubakhti (d. before 300H).

9. The Sab'iyyah also said that they came upon revelation and hidden knowledge that the people never encountered. They said that the Messenger of Allaah (sallallaahu alayhi wasallam) concealed nine tenths of the revelation. The grandson of Ali, al-Hasan bin Muhammad bin al-Hanafiyyah (d. 100H) refuted them on this matter in his treatise Risaalah al-Irjaa'.

Note that these details are found in the early Shia sources starting from the third century hijrah and from the writings of the grandson of Ali (radiallaahu anhu) in his Risaalah al-Irjaa' from before 100H who freed himself from the Sab'iyyah and their evil doctrines. These ideas and doctrines laid the foundations for the various sects of the Shia, Raafidah, and thus it is indeed a historical fact, that the true and real founder of the Raafidah Shia is Abdullah bin Saba' al-Yahudi.

Refer to:

• The Shia sources listed in this article, in particular the works of al-Qummi and al-Nawbakhti (see this article), and al-Rijal of al-Kashi, these are all early Shia authors and resources.
• Tarikh Dimashq of Ibn Asaakir
• Al-Durr al-Manthoor of al-Suyuti.
• Through Ibn Saba' Haqiqah Laa Khiyaal of Sa'di al-Haashimee.