<![CDATA[Purpose of the study: This study describes and analyzes how böwö, the customary bridewealth of Nias marriage, is understood in traditional and contemporary settings, and explains the shift between these meanings among the congregation of Banua Niha Keriso Protestan Church, Lotu, using Max Weber's theory of rational social action. Methodology: This qualitative study, conducted in 2026, used a critical-ethnographic design. Primary data were collected through unstructured in-depth interviews, document analysis, and participatory observation involving seven purposively selected informants: two church leaders, three customary leaders, and two congregation members in Lotu, North Nias Regency. Data were interpreted through Weberian Verstehen and coded against Weber's ideal types of social action. Main Findings: Böwö has shifted from value-rational (wertrational) action rooted in love (masi-masi) and communal solidarity to instrumental-rational (zweckrational) action, its value now calculated from a bride's education, occupation, and family status. Masi-masi rhetoric persists even as practice has become calculative, a mismatch linked to elopement, debt-driven poverty, and tension between customary and church authority. Novelty/Originality of this study: Unlike prior böwö studies grounded in theology or ethnography, this study sustains Weber's typology of social action as a analytical framework across an entire empirical case. Its original contribution is not simply applying the typology to a case, but showing how value-rational language can persist as a legitimating shell around instrumental-rational practice, extending Weberian rationalization theory beyond its usual macro-institutional settings.]]>
