The figure of Moses is marked in Freud's work by doubles and duplication: Freud's doppelganger, Moses reappears significantly in two instances more than twenty years apart (« Michelangelo's Moses », 1914 and Moses and Monotheism, 1938). What dazzles or fascinates in Moses is related to the mark of a paternal transmission, a transmission that is largely unconscious and whose meaning and valence are less obvious than one might think. The biblical and even more historical character of Moses exerts on Freud a powerful and complex attraction for reasons that this article attempts to bring to light: Moses is the name of a specific renunciation, understood as a factor of civilization, but even more so, because Freud considers him Egyptian, Moses is the very figure of the unknown from within, the unconscious.