Is the higher the positive organizational variable in the organization, the better? Based on the theory of Pierce and Aguinis (2013), who proposed the Too-much-of-a-good-thing effect, this study is designed to verify how organizational commitment, which was considered a positive organizational variable in organizational studies, affects the organizational effectiveness and the moderating effect of workplace spirituality as a moderating variable in that relationship. In order to achieve this research purpose, a survey was conducted on organizational members working in corporate organizations, and the data of the final 496 people were analyzed. As a result, under the condition of low workplace spirituality, it was confirmed a nonlinear relationship in which job motivation increases and then decreases as over-organizational commitment increases. However, under the condition of high workplace spirituality, a relationship was discovered in which job motivation nonlinearly increases as over-organizational commitment increases. Based on these results, the meaning, implications, and limitations of the study, as well as future studies, are all discussed.