The article is devoted to the analysis of modal constructions with infinitives in -(i)tuṃ in Pali, which is a representative of the early-middle stage of Indo-Aryan. Pali is predominantly known as the classical language of the religious and philosophical canon of «Theravada» Buddhism. As the most frequent suffix in Pali, -(i)tuṃ (historically, an indicator of a verbal noun frozen in the accusative) was also the most productive way of generating infinitives in classical Sanskrit (but the least productive in Vedic). Upon analyzing the Pali jatakas (fables about the Buddha’s earthly reincarnations) the author has identified a limited set of stable semo-syntactic contexts in which infinitives in -(i)tum occurred most frequently. The constructions discovered were analyzed and systematized throughout the prism of the functional-semantic field of modality.