How do we know Jesus has authority over evil spirits?

In Luke 8:30-33, we see Jesus confronting the man possessed by multiple demons, who identified himself as Legion. When Jesus commanded the unclean spirits to leave the man, they had no choice but to obey, illustrating His sovereign authority over demonic forces. This event showcases that nothing can oppose the command of Christ, affirming His role as Lord and Savior. His victory over evil spirits serves not only to deliver individuals but also to illustrate His power over sin and death, establishing Him as the one who liberates humanity from spiritual bondage.