Abstract. – This article challenges Claude Levi-Strauss’ and Philippe Descola’s diagnosis of the South American tropics, according to which the irreversible influences of the Western civilization have led to cultural homogenization and to the loss of autochthonous “originality.” This author discloses local reactions to global impacts as appropriation processes and emphasizes the natives’ agency. The missionary presence in the Ecuadorian Amazon has strongly influenced the native cosmology of the Achuar and Shuar, to which Descola particularly refers. However, Jesus has not replaced the indigenous spiritual power called Arutam. Rather the contemporary role and function of Jesus and Arutam exemplify the negotiation of cultural meanings. The article further analyzes the transcultural conditions of this appropriation and focuses on the inner logic of the indigenous and missionaries who create and define these new meanings. It demonstrates that the expression “Jesus is the same Arutam” does not necessarily illustrate the assimilation effects of cultural contact but rather the openness of cultural systems and the creative “originality” of the actors involved. [Ecuador, Amazonia, Achuar, Shuar, cultural contact, indigenization of Christianity, transculturation]