In order to examine the clinical experience of analytic thinking when the encounter with the patient involves the presence of a forbidden language and an extra-European world, the article presents two situations organized around consecutive oral translation: an interview situation with an interpreter and an inter-analytic situation of research. This work explores how the thinking of the interpreter and that of the analyst/interpreter make it possible to understand the possibilities of transformation between analyst and patient. For the analyst, the obstacles to translation allow, retrospectively, once translated, an enlarged access to the analyst’s countertransference and a way out of impasses in treatment. An analysis of the experiences reported sets out and clarifies the different expressions of the process of differentiation, including detranslation. After the studies on multilingualism in analysis, the recognition of heterolingualism may be an invitation to turn towards the new paths of translation studies.