Philippians 4:4-8 ESV
Rejoice in the Lord always; again I will say, rejoice.  Let your reasonableness be known to everyone. The Lord is at hand;  do not be anxious about anything, but in everything by prayer and supplication with thanksgiving let your requests be made known to God.  And the peace of God, which surpasses all understanding, will guard your hearts and your minds in Christ Jesus.  Finally, brothers, whatever is true, whatever is honorable, whatever is just, whatever is pure, whatever is lovely, whatever is commendable, if there is any excellence, if there is anything worthy of praise, think about these things.
If we’re being honest with ourselves, most of us aren’t who or what we think we are. Our thinking is marred at best, off-track, and in most cases, needs to be changed.
How do I know this to be true? God’s Word calls us to a “renewal” of our minds. That means trading in our old perceptions, opinions, ideas, beliefs, and self-centered attitudes for a new set of perceptions, opinions, ideas, beliefs, and attitudes that God develops in us. These godly responses are nurtured by regular reading of Scripture and meditating on what’s been read in the Bible. Christ’s followers are urged to avoid being “conformed to this world, but be transformed by the renewing of your mind, that you may prove what is that good and acceptable and perfect will of God” (Romans 12:2).
Out of a renewal of our thinking comes a change in our speech patterns and our behaviors. As our speech and behavior become renewed, our relationships with others become renewed. And as our relationships become renewed, our immediate world is renewed as well. It all begins in the mind with what we choose to think and what we choose to dwell upon.
You have the ability to determine what you think. At any time, you can refocus your mind to a new topic, task, or problem to solve instead of negative thinking that will steal your peace and/or cause you to venture into rebellion or sin. You have the ability to say, “I choose to trust God,” in any situation you face or think you have.
Furthermore, any child of God who takes a willful stand against thought patterns that clearly are harmful is going to be provided a way of escape from that circumstance. God will help you focus your mind on something other than your problem or bad thought pattern.
When you guard your mind, you protect your peace. When you offer prayers to God with faith and thanksgiving—no matter what trials you face—He assures you inner peace (Philippians 4:6-7). And when you focus your thinking on what’s true, noble, virtuous, lovely, pure, and praiseworthy, you rely upon God with increasing faith and trust.
You can never fully exhaust your ability to think about the goodness and greatness of God. Choose to respond to life the way Jesus responded. Guard your prayer life. Guard your thought life. Seek the Father and all that’s godly. His Word promises that when you fill your mind with what is virtuous and praiseworthy, “the God of peace will be with you” (Philippians 4:9).
To God be the glory. Great things He hath done.