This study developed a mediation model explaining how a sense of purpose and perceived inclusiveness can enhance organizational commitment by way of perceived organizational support and employee engagement. We tested the model with data collected from 722 employees representing 214 diverse companies. Our findings demonstrate that both personal and organizational purposes, along with inclusiveness, heighten organizational commitment through the avenues of perceived organizational support and engagement. Furthermore, our finding reveals that perceived organizational support influences engagement, rather than the reverse. This study underscores the significance of a sense of belonging within the organizational boundary. Purpose, inclusiveness, and perceived organizational support all promote a profound sense of belonging with the organizational boundary. The psychological sense of belonging elicits the space for employees to exercise ownership for engagement. Drawing upon these findings, we further discussed their theoretical and practical ramifications.