BACKGROUND: The Christian Sanctification of Suffering Scale (CSSS) measures the extent to which individuals interpret suffering as spiritually meaningful within a Christian framework. This study aimed to adapt and psychometrically validate the CSSS in Polish. METHODS: The study involved a community sample of Polish adults living with chronic pain lasting longer than six months, all identifying as Catholic. Participants completed a 30-minute online survey including the CSSS along with validated measures of religious commitment, spiritual well-being, mental health, and forgiveness. Three months later, a subsample completed the CSSS again to assess temporal stability. The CSSS was translated into Polish and evaluated using confirmatory factor analysis (CFA), item response theory (IRT), reliability analysis, and measurement invariance across sex. RESULTS: The CSSS demonstrated a unidimensional structure, confirmed by CFA (χ = 39.62, p = .056, CFI = 0.941, TLI = 0.921, RMSEA = 0.071, SRMR = 0.033, and GFI = 0.92), and showed excellent internal consistency (α = 0.92). IRT analyses indicated strong item discrimination and a broad range of item difficulty. Measurement invariance across sex was confirmed, and female participants scored significantly higher. Convergent validity was supported through significant correlations with spirituality, religious engagement, mental health indicators, and forgiveness. The scale also demonstrated high temporal stability over a three-month interval. CONCLUSIONS: The Polish version of the CSSS is a psychometrically robust instrument for assessing the sanctification of suffering. It offers a novel instrument for assessing spiritual coping, with potential implications for designing spiritually sensitive clinical interventions.