When that caliphate failed...
When that caliphate failed, its dignity was lost, ending in the hands of the Mamlukes and non-Arabs, and there were those who were heard calling for the documenting of the Prophetic Sunnah..., it was only then that such traditions, which former generations tried very energetically to obliterate and hide but could not do so, in addition to those particular traditions persisted as puzzles mystifying them: they contradicted their beliefs at that time.
Some of them tried to reconcile those traditions with their beliefs, so they pretended to love ; therefore, whenever the name of Imam Ali is mentioned, they would say, "May Allah be pleased with him," or "Allah glorified his countenance," so that people might get the impression that they were not the enemies of the House of Prophethood.
None among the Muslims, not even the hypocrites among them, can demonstrate his enmity towards the Prophet's family because the enemies of are the enemies of the Messenger of Allah, and such enmity will eject them from the Islamic fold altogether as is obvious.
What we can understand from all of this is that they, in reality, are, indeed, enemies of the Prophet's family, and by "they" we mean the "good predecessors" who adopted the label of, or who were labelled by their supporters as, "Ahl al-Sunnah wal Jama`a." Another proof is that you can find all of them following the four sects which were created by the ruling authority (as we will soon prove), and they have nothing in their religious injunctions to which they can refer such as the fiqh of , or of any of the Twelve Imams.
The truth mandates that Imamite Shi`as are actually the followers of the Sunnah of Muhammad because they upheld in all their juristic injunctions the teachings of the Imams of who inherited the authentic Sunnah from their grandfather the Messenger of Allah without mixing it with their own personal views, opinions, or the statements of the caliphs.
Shi`as remained across the centuries upholding these texts and rejecting the concept of ijtihad in the presence of clear traditions, believing in the caliphate of Ali and his offspring because the Prophet had clearly indicated so. They, therefore, call them the caliphs of the Messenger of Allah although only Ali had the chance to be the actual caliph.