2 Cor. 10:4-5 (NIV)
The weapons we fight with are not the weapons of the world. On the contrary, they have divine power to demolish strongholds.  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
Dealing with the mental strongholds in our thinking is really a battle. Here are some thought we need to take captive.
Proverbs 16:18 (NIV)
Pride goes before destruction, a haughty spirit before a fall.
Pride is one of those protected thoughts we have to deal with. Like the young woman who went to her pastor and said, "Pastor, I have a besetting sin, and I want your help. I come to church on Sunday and can't help thinking I'm the prettiest girl in the congregation. I know I ought not think that, but I can't help it. I want you to help me with it." The pastor replied, "Mary, don't worry about it. In your case it's not a sin. It's just a horrible mistake."
A proud person WILL fall.
It is like the law of gravity. It will happen.
Unbelief tells us it will not work to be a Chrisitian. "All this serving God stuff is just a waste." It will tell us. "Look at all those people doing whatever they want, and they are still living a good life."
Psalm 73:3 (NIV)
For I envied the arrogant
when I saw the prosperity of the wicked.
Psalm 73:12-13 (NIV)
This is what the wicked are like--
always carefree, they increase in wealth.
 Surely in vain have I kept my heart pure;
in vain have I washed my hands in innocence.
Sounds like a battle in thoughts to me. But the truth is:
Psalm 73:27 (NIV)
Those who are far from you will perish;
you destroy all who are unfaithful to you.
When you fear that the worst will happen, your own thoughts may help to bring it about. “Fear,” a writer once said, “is the wrong use of imagination. It is anticipating the worst, not the best that can happen.”
A salesman, driving on a lonely country road one dark and rainy night had a flat. He opened the trunk—no lug wrench. The light from a farmhouse could be seen dimly up the road. He set out on foot through the driving rain. Surely the farmer would have a lug wrench he could borrow, he thought. Of course, it was late at night—the farmer would be asleep in his warm, dry bed. Maybe he wouldn’t answer the door. And even if he did, he’d be angry at being awakened in the middle of the night. The salesman, picking his way blindly in the dark, stumbled on. By now his shoes and clothing were soaked. Even if the farmer did answer his knock, he would probably shout something like, “What’s the big idea waking me up at this hour!”
This thought made the salesman angry. "What right did that farmer have to refuse him the loan of a lug wrench? After all, here he was stranded in the middle of nowhere, soaked to the skin. The farmer was a selfish clod—no doubt about that!" The salesman finally reached the house, and banged loudly on the door. A light went on inside, and a window opened above. “Who is it?” a voice called out. “You know darn well who it is,” yelled the salesman, his face white with anger. “It’s me! You can keep your blasted lug wrench. I wouldn’t borrow it now if you had the last one on earth!”
Proverbs 10:24 (NASB)
What the wicked fears will come upon him,
And the desire of the righteous will be granted.
If we serve God, we do not have to fear anyone or anything else. Especially not people. History is loaded with individuals who sold their lives because they feared what others would think of them. Pontius Pilate sold his soul and had the Son of God crucified because he did not want the people to dislike him.
Proverbs 29:25 (NIV)
Fear of man will prove to be a snare,
but whoever trusts in the Lord is kept safe.
The way God wants us to think is, "If God likes me, I do not care if others do not!” What a relief!!
God never intended us to live timid fearful lives. Instead His plan for us to live exciting, successful lives filled with enthusiasm.
2 Tim. 1:7 (NIV)
For God did not give us a spirit of timidity, but a spirit of power, of love and of self-discipline.
Taking these thoughts captive is well worth the effort. Living free from pride and fear is what God planned for us.