Since self-efficacy is a positive predictor of substance use treatment outcome, we investigated whether it is associated with spirituality within a religious 12-step program. This was a cross-sectional survey (N = 91) of 10 different Celebrate Recovery sites held at community churches. The mean spirituality score for those with high confidence was significantly greater than those with low confidence. Spirituality associated with greater confidence to resist substance use (OR = 1.09, 95% CI 1.02-1.17, P < 0.05). So every unit increase of measured spirituality increased the odds of being above the median in self-efficacy by 9%. We conclude that spirituality may be an important explanatory variable in outcomes of a faith-based 12-step recovery program.