["Journal of the American Geriatrics Society, Volume 74, Issue 4, Page 1141-1162, April 2026. ", "\nABSTRACT\n\nBackground\nWith an aging population globally, the number of older adults living with chronic diseases has increased. There is limited understanding of how spirituality and religiosity are pivotal for resilience among older people dealing with the burden of managing chronic illnesses.\n\n\nObjective\nTo systematically identify, synthesize, and critically appraise the current evidence on how spirituality and religiosity serve as sources of resilience among older adults with chronic illness.\n\n\nMethods\nThis review was registered with PROSPERO (CRD420250645463). Several online databases (PubMed, MEDLINE (Ovid), APA PsycINFO, and CINAHL) were searched from database inception to March 2025. Included articles were peer‐reviewed, published in English, had adults aged ≥ 60 years with chronic conditions, and reported quantitative or qualitative findings on participant experiences and influence of spirituality and religiosity. The methodological quality of each included study was assessed. The qualitative and quantitative findings were analyzed separately, followed by an integrated analysis.\n\n\nResults\nTwenty‐six articles (21 quantitative and 5 qualitative) were included. Most of the studies were conducted in the United States and among predominantly Christian populations. Varying measures were utilized in assessing spirituality and religiosity. From the integrative synthesis of both studies, spirituality and religiosity served as a source of resilience for older adults through four overarching domains: (i) Spiritual connection as a source of strength; (ii) Meaning, purpose, and life satisfaction through spiritual beliefs; (iii) Combining spirituality and medical care; and (iv) Faith communities as social support networks.\n\n\nConclusion\nSpirituality and religiosity are important, yet underutilized, resources that promote resilience in older adults with chronic illness. Greater clinical attention to spiritual assessment, integration into chronic disease care, and referral for clerical intervention when indicated may enhance patient‐centered outcomes. Future research should increase representation of diverse religious perspectives, ensure uniformity in assessing spirituality/religiosity to enhance comparability across studies, and explore clinician preparedness to deliver holistic care.\n\n"]