The second century was the period of formation and expansion of theological knowledge and emerging intellectual currents. Theological, hadithic, and historical data show two apparently contradictory approaches of Imam Sadiq (peace be upon him) towards theology—from prohibition to emphasis—so much so that some of his companions noted this discrepancy. This interdisciplinary study, using a descriptive-analytical method, explores this approach and finds that Imam Sadiq’s stance was not contradictory but a wise, multifaceted, and intelligent management according to the subject, audience, and method: On one hand, he severely condemned metaphysical theological discourse beyond reason, such as the essence of God and the use of invalid methods like analogy. On the other hand, by training theologians like Hisham ibn Hakam and encouraging systematic debates based on Quran and Sunnah, he emphasized the need to explain and defend the authentic Shiite view rationally against others. Consequently, Imam Sadiq established a principled and balanced framework for Imamiyyah theology, founded on rationality and revelation, profoundly influencing its later developments.