The article deals with two problems: the character of dictatorship with religious purposes (especially clavi figendi causa) and the sacral content of dictio. The research has shown that religious tasks fulfilled by dictators belonged to the consul’s competence, as well as in other cases of dictatorship imminuto iure. This can also apply to the rite of «driving a nail», an extraordinary magical ritual. Its association to the dictator’s power was due to a precedent fixed because of the sacral principle post hoc ergo propter hoc. Religious requirements during dictio referred not to dictio itself but to the auspices preceding it. Essentially, the act of dictio did not differ from that of renuntiatio of the winner at the electoral comitia. It has nothing to do either with the cooptation or with the inauguration of a priest. The sacral content of dictio was in principle like any other action of the consul. Consuls’ exclusive right to appoint dictators can be explained by the original sacral and political status of this republican magistrate as successor to the royal power. The absence of clear and definite data as to the magical content or perception of magistrates’ power is due to the processes which had first led to the expulsion of the kings and then to the development of civitas.