This article examines the development of a Marxian frame for the critique of religion in twentieth century Iranian political thought by Taqi Erāni and Bizhan Jazani. It argues that, following Marx, Erāni and Jazani understand religion to be a superstructural relic from an earlier stage of human development which will gradually and inevitably withdraw from collective human life as a consequence of the material dialectics of history. It further shows that Erāni and Jazani consider religion to be instrumental in sustaining relations of oppression, and they view with skepticism attempts to reform religion or to use religious faith as an instrument for mass mobilization in revolutionary struggles.