Arabic language learning in Indonesian pesantren has traditionally emphasized mastery of grammar, morphology, vocabulary, and classical texts; however, many non-native learners still experience a gap between linguistic competence and spontaneous communicative performance. This gap is intensified by the limited availability of authentic Arabic-speaking environments in domestic educational contexts. This research aims to analyze how a High-Context Culture is established, maintained, and experienced in Arabic language learning, and to formulate an ecological model that explains its role in enhancing the communicative performance of non-native speakers. The study was conducted in the LPBAA Daerah Arab Dormitory of Sidogiri Islamic Boarding School using an educational ethnographic approach. Data were collected over a six-month period through in-depth interviews with four administrators, three students, and two senior students serving as Rijalul Lughah, along with participant observation and document analysis. The findings reveal that Arabic communicative performance is shaped by a multi-layered ecological architecture consisting of five interconnected components: compulsory linguistic zones, a performance-based spiral curriculum, a time-layered activity network, the social infrastructure of Rijalul Lughah, and an authentic resource ecosystem. This culture is maintained through gradual socialization, educative correction, hybrid motivation, and communal identity-reinforcing rituals. The analysis shows that the high-context learning culture increases students’ willingness to communicate, strengthens pragmatic-intercultural competence, supports the acquisition of contemporary Arabic expressions, and transforms Arabic from a classroom subject into a medium of social participation and identity formation. The study contributes to Arabic language learning theory by integrating Sociocultural Theory, Community of Practice, and High-Context Culture into an ecological model of designed domestic immersion.