Having disarmed principalities and powers, He made a public spectacle of them, triumphing over them in it. Colossians 2:15 (NKJV)
Walking in victory over the devil, his demons and all their works starts with this knowledge that God in Christ already defeated and disarmed them.
We are dealing with a powerless, conquered foe.
Ephesians 6:12 talks about wrestling with principalities and powers but the verse above it – Ephesians 6:11 clearly let’s us know that our wrestling is against the wiles, tricks, or deception of Satan. We wrestle against the devil’s lies by standing and fighting with the Truth. The number one truth in fighting or standing against these principalities and powers is that Jesus already on the Cross defeated and disarmed them. They have no power over us. We have and walk in power over them. Jesus has all authority and power and in His Name we have all authority and power.