Al-Mahdi, the Imamate, and the Bay'ah: A Critical Hadith Analysis in Twelver Shiite and Sunnite Canonical Literature

This piece of research analyses nineteen twelver and sunnite hadiths and their ninety narrators in order to answer the research question here, which is how, and maybe since when, twelver and sunnite hadith collections have had similar and identical hadiths? The research attempts to answer this question by suggesting possible explanations for the research problem, which is having similar and identical hadiths between twelver and sunnite hadith collections. This is problematic because having such hadiths is not expected, as the expectation is to have two corpora of completely different hadiths. This is so because of the differences between twelver shiism and sunnism and their hadiths, the most important of which are having generally different sources of hadiths and that each school has different collections of hadiths.
The nineteen hadiths include ten hadiths in al-Kāfī and three in Ṣaḥīḥ Muslim on warning of mītah jāhilīyah if someone died without having an imam or bay'ah. The remaining six hadiths comprise three hadiths in al-Kāfī and other three in Sunan Abī Dāwūd on al-Mahdī.
Possible explanations for the research problem are, one, the possibility of narrating the hadiths using their meanings instead of their exact texts, and, two, the possible influence of common links, in a general sense, such as al-Zuhrī, and of the affiliations and places of the narrators on narrating twelver as well as sunnite hadiths.
In addition, this research redefines jāhilīyah, walāʼ, and being a mawlá. Each of these terms has multiple and different meanings. Furthermore, it is argued here that the four identities offered for a narrator called 'Abd al-A'lá are likely to have been of one narrator called 'Abd al-A'lá ibn A'yan, and therefore, he could have been an Arab and a mawlá with four tribal associations and a sunnite as well as a shiite.