We demolish arguments and every pretension that sets itself up against the knowledge of God, and we take captive every thought to make it obedient to Christ. 2 Corinthians 10:5
We must guard against 'Rogue" thoughts that enter our mind and cause us to take actions or develop ideas that are against the knowledge of God.
We often feel and act passively about our thoughts; we feel thoughts and emotions are a normal thing and we have no control over them. On the contrary we do. Our mind is not a loose cannon able to run freely and deposit unwholesome thoughts that can ultimately destroy us.
God in His wisdom, gave us weapons to recognize when our mind has strayed away from the teachings of God. He said we must "hold every thought captive". We have that ability. The most powerful weapon that satan has in his toolbox is to capture our mind.
Think about it, how often do you struggle with controlling your thoughts? It is a constant struggle. Primarily because you are not exercising the shield of faith that God has given to you.
Ephesians 10: 13 " Put on the full armor of God, so that when the day of evil comes, you may stand your ground, after you have done everything to stand.
We are in spiritual warfare against the devil, do not forget that, and his main tactic is to take control of our minds. You must be constantly equipped with spiritual weapons to fight the schemes of the devil
Finally, be strong in the Lord and in his mighty power.
Ephesians 6: 18
11Put on the full armor of God so that you can take your stand against the devil's schemes. 12For our struggle is not against flesh and blood, but against the rulers, against the authorities, against the powers of this dark world and against the spiritual forces of evil in the heavenly realms. 13Therefore put on the full armor of God, so that when the day of evil comes, you may be able to stand your ground, and after you have done everything, to stand. 14Stand firm then, with the belt of truth buckled around your waist, with the breastplate of righteousness in place, 15and with your feet fitted with the readiness that comes from the gospel of peace. 16In addition to all this, take up the shield of faith, with which you can extinguish all the flaming arrows of the evil one. 17Take the helmet of salvation and the sword of the Spirit, which is the word of God. 18And pray in the Spirit on all occasions with all kinds of prayers and requests. With this in mind, be alert and always keep on praying for all the saints.