Abstract The principle of "necessity of Aliallah" is in line with the rules of knowledge of theology and is based on the thought of reasoning the goodness of the verbs. For the applications that are in the domain of verbal issues, this rule needs to be clarified to what extent the theological issues of the Imamite theologians have been used and on what issues of theological doctrines have been used. The present paper, in a library style and with an analytic report approach, has expanded the scope of the rule in the field of word science. With the study of the scientific traditions of the famous theologians of Imamieh, it became clear that the principle of "necessity of Allah" in matters such as duties, grace, prophets, prophets, miracles, imamate, Imam's infidelity, invalidation, resurrection, punishment, vindication, antithesis And the divine reward is effective and the Imamite theologians have applied it on these issues.