In modern Shi’i Islam, power constitutes a major concern for thinkers and movements alike. Above all, Muham mad Husayn Fadlallah stands as the most systematic Shi’i thinker who produced an Islamic theory of power. The present article analyses Fadlallah’s concept of social power. In Islam and the Logic of Power (al-Islam wa-mantiq al-quwwa), he emphasised the importance of social solidarity, justice, and the obligation of “commanding right and forbidding wrong” as a means to create the ideal society. For him, this social model has are ciprocal relation to social power. Muhammad Husayn Fadlallah tells the tale of two societies: the weak and the strong, arguing that beliefs, unity and values determine the power of a community. He claims that the strong society is best illustrated by the first Islamic community. He confronts it with the weak society which lacks unity and solidarity — echoing to a great extent contemporary Lebanon. Fadlallah’s social theory — embedded in his theology of power — transforms spiritual power into a collective deployment of action. He draws on a wide range of elements (Sunni, Shi’i and Marxist) to create a coherent system of power in which social power is a mediator between the ideology of power and its political manifestation.