Why does Captain Auld sendfredrick Douglass back to Baltimore?

Captain Auld sends Frederick Douglass back to Baltimore to work as a laborer in order to exert control over him and to exploit his labor. Auld believes that Douglass will be more manageable and profitable in a familiar environment where he had previously worked. This decision reflects Auld's interest in maximizing his economic gain while maintaining the institution of slavery. Ultimately, it serves as a pivotal moment in Douglass's journey toward self-awareness and eventual escape from bondage.