Adolescents and emerging adults are still learning how to manage their emotions, and for most young people worldwide, faith and spiritual life are part of how that learning happens. Emotional regulation (ER) is usually defined as the set of processes people use to influence which emotions they have, when they have them, and how those emotions get expressed. Spirituality and religiosity (R/S) are among the resources young people lean on most heavily to do this work, yet the two literatures — developmental ER research and the psychology of religion — have only recently started talking to each other. This review pulls that conversation together for readers interested in the roughly ages 10–29 window. Drawing on Gross’s process model of ER and Pargament’s theory of religious coping, four mechanisms are examined: meaning-making and cognitive reappraisal, religious and spiritual coping, attentional or self-regulatory training through contemplative practice, and relational processes built around a perceived sacred other. Across correlational, longitudinal, and intervention studies, R/S tends to correlate, modestly to moderately, with more reappraisal and less rumination or suppression, and ER often mediates the path from R/S to lower risk-taking, less depression and anxiety, and greater life satisfaction. None of this holds unconditionally, though: negative religious coping and spiritual struggle reliably predict worse outcomes, and the size and even direction of effects shift with developmental stage, culture, and religious tradition. The review ends by naming the field’s main methodological gaps — heavy reliance on cross-sectional designs, inconsistent measurement, and thin cultural representation — and suggesting where longitudinal, neurobiological, and intervention work could go next.