Rubuta ci gaba don wannan sakin layi - A akida, al-Mu'tasim ya bi sawun al-Ma'mun, yana ci gaba da goyon bayan magabata ga Mu'tazilism, wata koyarwar tauhidi da ta yi ƙoƙari ta bi hanya ta tsakiya tsakanin mulkin mallaka na duniya da tsarin mulkin Allah wanda Alids da ƙungiyoyi daban-daban na Shi'ism suka yi. Mu'tazilis ya goyi bayan ra'ayin cewa an halicci Kur'ani kuma saboda haka ya faɗi cikin ikon Allah-wanda aka jagoranta "imām" don fassara bisa ga yanayi mai canzawa. Duk da yake suna girmama Ali, sun kauce wa ɗaukar matsayi game da adalcin bangarorin da ke adawa da juna a cikin rikici
tsakanin Ali da abokan hamayyarsa. Mu'tazilism ya karɓa a hukumance ta al-Ma'mun a cikin 827, kuma a cikin 833, jim kaɗan kafin mutuwarsa, al-Ma'mun ya sanya koyarwar ta zama tilas, tare da kafa wata kotu, "miḥna". A lokacin mulkin ɗan'uwansa, al-Mu'tasim ya taka rawar gani wajen aiwatar da "miḥna" a lardunan yamma; wannan ya ci gaba bayan hawansa. Babban mai ba da shawara ga Mu'tazilism, babban "qādī" Ahmad ibn Abi Duwad, wataƙila shine babban tasiri a kotun khalifa a duk lokacin mulkin al-Mu'tasim.