Objectives We have previously reported that a multifaith spiritually based intervention (SBI) may have efficacy in the treatment of generalized anxiety disorder (GAD). This randomized pilot trial tested whether the SBI had greater efficacy than a nonspecific control condition in GAD. Method Twenty‐three participants with GAD of at least moderate severity were randomized to 12 individual sessions of the SBI (n = 11) or supportive psychotherapy (SP)—our control condition (n = 12). Results Intent‐to‐treat analysis revealed the SBI fared better than SP in decreasing blind clinician ratings of anxiety and illness severity and self‐report worry and intolerance of uncertainty, with large between‐group effect sizes. The SBI also produced greater changes in spiritual well‐being. Results remained the same when supplementary analyses were performed on the completer sample. Treatment gains were maintained at 3‐months follow‐up. Conclusions This small pilot trial demonstrates that a nondenominational SBI has greater efficacy than a rigorous control in improving symptoms of GAD and enhancing spiritual well‐being. These results are encouraging and further research on the efficacy of the SBI and its underlying mechanisms is warranted.