(Taken from a Bible Study preached on 16th September 2026.)
“Casting down imaginations, and every high thing that exalteth itself against the knowledge of God, and bringing into captivity every thought to the obedience of Christ.”
2 Corinthians chapter 10 verse 5
The thought life of the believer is a subject in which we can all too easily drift into homespun psychology. To avoid this, we will confine ourselves to a number of biblical texts that speak directly or indirectly to the management of the thinking of the believer. This will help us to consider only those exhortations that bring the stamp of divine authority, and are not merely human ideas.
We begin with the apostle Paul speaking about his own work and ministry. The context (from 2 Corinthians chapter 6) is the problem of false teachers and their wrong ideas creeping into the church. In this context Paul says that his work involves “casting down imaginations” (opinions that are contrary to the Word of God) along with “every high thing” (fine-sounding claims that challenge the truth).
Paul’s words provide a guiding principle for us all, as believers. We have to weed the garden of the thought life and close the front door of the mind to the ‘wild beasts’ of harmful heresies and distractions that roam nearby.
The imaginations and high things invading our thinking may be temptations, inclinations, or hostile or unclean practices. They may equally be selfish, self-pitying or proud thoughts. They might focus on delights and entertainments, and hobbies and pursuits that grip and consume inordinate amounts of time, money and attention. They may be murmurings and resentments.
Wrong and inappropriate thoughts ‘exalt’ themselves or ‘lord it over’ good and godly thoughts, bringing us into spiritual backsliding. Paul says they must be ‘cast out’ – a decisive, forceful act. In Romans he says, ‘mortified’ or put to death.
We are never exhorted to crush our imagination, but if it presents things which destroy or detract from our spiritual life we are to bring those thoughts into captivity, terminating their activity. Paul uses the imagery of warfare—it is not a gentle exercise.
The thought life is so important, yet we can allow hours and months and even years to go by with scant control of it, while diversions, complaints, self-seeking ideas, and desires driven by pride and covetousness brew freely. All such things should be recognised quickly and mortified.
Thoughts are a choice
At this point we turn to the Old Testament, to Deuteronomy 30:19, to read the famous challenge of Moses: “I call heaven and earth to record this day against you, that I have set before you life and death, blessing and cursing: therefore choose life, that both thou and thy seed may live.”
Obviously this is a verse about choice. It’s addressed to the children of Israel, the typical church of the Old Testament, a people who illustrated and represented the redeemed of the Christian age—as the apostle says, these things were “written for our learning” (Romans 15:4). We are commanded to “choose”—an ability that marks us out from the entire animal kingdom. We choose with the rational faculty, the mind being the organ of choosing and the palace of faith.
Moses called the people to make a choice: to follow God for life and blessing, or to opt for disobedience, death and cursing. Believers have been brought by the regenerating work of the Holy Spirit to make that choice at conversion, but the choosing process goes on throughout life. Every hour is an hour of choosing ideas and actions relating to blessing and life, or those relating to death and cursing. The text lives on daily in our lives, “Choose you this day whom ye will serve” (Joshua 24:15).
From the moment a day opens, we are confronted with choices about temptations, suggestions, complaints, desires, entertainments, and so on. They must be evaluated, and we must choose life, the Word of God, the things of God, and the service of God.
Many of the thoughts we reject will not be intrinsically sinful, but they will be conducive to death rather than life. They will distract and divert us from our primary objective to live for the Lord, so we must pray and reject them. For how long a time have we been neglecting this? For how long have wrong aims and desires, injurious and hurtful words, walked freely into the house of our mind? Every day we will be presented with these choices, but our assignment from the Lord is ever to choose life.
Moses exclaimed: “I call heaven and earth to record this day against you”, reminding us that we are being watched, not only by the Lord, but by Satan and his hosts. Demons of darkness watch for every slip, every bad decision, to determine whether we can be pushed even further down some unspiritual route, and brought to shame.
The Holy Spirit within us warns us, stirring our conscience, but perhaps we suppress his motions, and succumb to the enemy. Moses’ prayer is, “that thou mayest love the Lord, obey his voice and cleave unto him.”
Guarding the mind
We proceed to Proverbs 4:23: “Keep thy heart with all diligence.” By heart is meant the central core of our being, ruled by the mind. “For out of it”, says the proverb, “are the issues of life”. The Hebrew word translated “keep” is guard. We are exhorted to protect our minds. We have moved from choosing to guarding, the mind being precious as the source of all our ideas and aspirations.
Here is the fountain-head of either self-serving sins, or of good works and words. The mind also clothes those thoughts and actions with love and warmth, or formality and coldness. If we fail to protect the mind our entire lives become tainted. With the Holy Spirit indwelling, good things come out of us like a well “springing up into everlasting life” (John 4:14).
Whatever seizes our imagination we ask: Should I be thinking these thoughts? If some terrible thing happens to us, we should ration our thinking about it, and commit the matter to the Lord to seek his rescue and strength. We guard the mind from ‘treadmill thinking’, or allowing morbid or bitter thoughts from constantly murmuring in the mind, because this changes us as people. We easily become negative, complaining, critical and faithless. We must protect ourselves at the thinking level, “with all diligence, for out of it [the mind] are the issues of life”.
If we pass on to Proverbs 23:6, we read “Eat thou not the bread of him that hath an evil eye, neither desire thou his dainty meats.” An evil eye today refers to a curse from the gods, but in the Bible it always means a covetous, greedy eye. Says Solomon, Do not closely associate with a covetous person “for as he thinketh in his heart, so is he” (verse 7). The person who is always grasping, and always wanting more, actually shapes his character by his desires.
So it is with believers. We covet things and the devil will fan the flames of desire until we are profoundly affected, and all our emotional energy is spent on our perceived needs and desires. Do we realise how deeply affected and changed we may be by that ‘idol’ that occupies the mind?
Solomon then adds a comment about deepening a friendship with a covetous person. He warns: “For as he thinketh in his heart, so is he: Eat and drink, saith he to thee; but his heart is not with thee.” That person has no capacity for friendship because he has been taken over by the lust of must-have more.
Once again we are shown that thoughts fashion us, so guard the mind. How much, also, we need to take charge of our daydreams, especially those that put us in the centre of whatever we are imagining, as the star or the hero or the triumphant one. Proud thinking makes proud people.
Resting the mind on the Lord
We turn next to Isaiah 26:3, “Thou wilt keep him in perfect peace, whose mind is stayed on thee: because he trusteth in thee.” The things that agitate us, and cause fear or anxiety, may be exchanged for peaceful trust in the Lord, but this requires an act of thinking management, a conscious turning of one’s preoccupation with the troubling issues, to reliance on the Lord.
The principle that thinking shapes character for better or worse is affirmed very clearly by the Lord Jesus Christ in Mark 7:20–23. Here we learn that whatever rules the thought life inevitably emerges in character and behaviour. The ‘heart’ represents the mind and affections. The Saviour says: “That which cometh out of the man, that defileth the man. For from within, out of the heart of men, proceed evil thoughts, adulteries, fornications, murders, thefts, covetousness, wickedness, deceit, lasciviousness, an evil eye, blasphemy, pride, foolishness: all these evil things come from within, and defile the man.”
In these words of the Lord we see the doctrine of concupiscence, referring to the evil desires and sins that flow from our corrupted human nature, original sin. The converted person has been forgiven, and delivered from the inevitable dominion or mastery of sin, and given a new nature that loves God.
But the old nature is still within, throwing up suggestions and desires, and these must be ‘mortified’ or put to death as they arise. If they are not, and the wrong thought is entertained or relished, or the wrong word uttered, and this pattern goes on, then sinful behaviour regains control, and the conscience is suffocated and silenced. Only by effort, joined with prayer to secure the help of the indwelling Spirit, will the burgeoning sin be stopped and crushed.
The famous words of Paul in Romans 7:20-23 show the intensity the battle may attain: “Now if I do that I would not, it is no more I that do it, but sin that dwelleth in me. I find then a law, that, when I would do good, evil is present with me. For I delight in the law of God after the inward man [the mind]: but I see another law in my members.” This other law he calls “the law of sin” which he serves “with the flesh” (verse 25), the flesh meaning his fallen human nature. It is still there, inside him, clamouring for attention.
If it were not for Christ sending the help of the Spirit, his situation would be hopeless, and he expresses this in the words, “O wretched man that I am! who shall deliver me from the body of this death?” But Christ has given his blood to secure our forgiveness and his Spirit to rescue and help us, so with tremendous relief and joy Paul can say, “There is therefore now no condemnation to them which are in Christ Jesus, who walk not after the flesh, but after the Spirit” (Romans 8:1).
Paul is a veteran saint, but in his ongoing Christian life he feels the weight of battle in his mind, the struggle with the suggestions of the old nature, corrupted by the law of sin. But with the blessing and the help of God he can put to death or put away the sinful desires and imaginations of the flesh. And if the holy apostle had to engage in this struggle, so must we.
It is both wrong and foolish to say that inward temptation is not sinful, and that only the action is sinful. It is wrong because so many wrong deeds begin as a thought or a lust, and the work of restraining and mortifying must begin there.
Put away wrong thoughts
In Ephesians 4:31–32 we are brought back to the activity of choosing whether to allow certain thoughts to continue or not. “Let all bitterness, and wrath, and anger, and clamour, and evil speaking, be put away from you, with all malice: and be ye kind one to another, tenderhearted, forgiving one another, even as God for Christ’s sake hath forgiven you.”
We must choose and determine to put away wrong ideas or they will get hold of us, and take over both thought and actions. Some believers stumble at this point, hanging on to negative, critical, complaining and self-pitying thoughts until Satan presses them to become utterly bitter people, and unbearable. So let us choose to end such persistent thinking, seeking the help of God to see matters in proportion, and to weigh and value our blessings.
Paul urges the terminating of all bitterness, and also of wrath, which refers to passion (getting really worked up). Be angry without sin, is the rule of Scripture, but passion takes us over. Anger quickly carries people far outside the bounds of reason and sense, and into the regions of sin and hurt. Choose, says Paul, to be kind, tenderhearted, forgiving one another, remembering that Christ has forgiven you. These are the vital actions of the Christian mind.
Marshalling the affections
The instructions of Philippians 4:8 will be elaborated on in another article, but here once again is the warrant for us to take charge of our thought agenda, coupled with practical counsel. “Finally, brethren, whatsoever things are true, whatsoever things are honest, whatsoever things are just, whatsoever things are pure, whatsoever things are lovely, whatsoever things are of good report; if there be any virtue, and if there be any praise, think on these things.”
What do our roaming minds venture into as we walk the pavement, sit on the train or bus, or lie awake? About what do we worry or grieve? What plans, dreams and hopes play out in our minds? Do we give room for focusing and reflecting on good, positive, constructive, beautiful, and spiritually significant things? Do we ever intentionally switch the mind to these things? The apostle urges: “If there be any virtue, if there be any praise, think on these things.”
The very next book, in effect, tells us the same: Colossians 3:2–5, “Set your affection on things above, not on things on the earth. For ye are dead, and your life is hid with Christ in God. When Christ, who is our life, shall appear, then shall ye also appear with him in glory. Mortify therefore your members which are upon the earth; fornication, uncleanness, inordinate affection, evil concupiscence, and covetousness, which is idolatry.” What a command verse 3 is to set before our eyes when we find ourselves liking something too much, and wanting it too much! It is surely a text to learn for use every day.
“For ye are dead” says Paul, referring to our legal position, the sin record of the old life having been cancelled at Calvary. But the old nature lingers within. The legal reality, he says, is hidden from view, in Christ, inscribed for ever in the Lamb’s Book of Life. Unconverted people (and we ourselves) cannot see the glory which clothes us in the mind of God and in the eternal future. Our life is hidden from mortal view.
“There goes a Christian,” our critic may say. “He is a religious fellow for whom I have no time.” It is not realised that the believer is already as good as glorified, made holy, filled with knowledge beyond human understanding, and brought into close fellowship with Christ. Legally it has already been accomplished. Soon it will be seen.
There is more to say, because the word ‘hid’ also holds the meaning that we are protected, surely kept, until the day when Christ appears and we appear with him in glory. The thought of our absolute security in Christ should motivate us to set our affections, riveting them, on things above.
Keeping a safe mind
There is another New Testament text to guide the thought life in 2 Timothy 1:7: “For God hath not given us the spirit of fear; but of power, and of love, and of a sound mind.” What is a sound mind? Sometimes the word “sound” in the KJV means healthy, but here it translates the Greek for safe. God has given us the spirit of a safe mind. Do we keep a safe mind?
Charismatic friends want the mind, or the rational faculty with self-control, to be taken out of the way so that they may become uninhibited and ready to let go, perhaps falling on the floor, or speaking in uncontrolled tongues, or dancing ecstatically. They like to be free from the direction of the mind, even welcoming trance-like states, and the seeing of visions or receiving of impressions.
But God has given the safe, rational, sensible mind, and this must always be operating or switched on. We are to be mature, responsible for how we think, using the mind in making the choices for the Lord that confront us daily. God will help and bless mightily if only we would be true to the spirit of a safe mind.
A cosmic view of the thought life
Here, to conclude, is a cosmic view of believers in Christ using their minds and hearts for the Lord. It is found in Psalm 46:10, “Be still, and know that I am God: I will be exalted among the heathen, I will be exalted in the earth.” At first glance this may not seem to be a psalm about the use of the mind, but an affirmation of God’s ultimate victory over sin, and his everlasting glory. But in reality it covers the whole of life. Verse 10 calls God’s people to “Be still!” Literally the Hebrew means: “Let your hands hang down!” or desist, stop striving. Stop and reflect, in order to grasp the might and majesty of God. “I am God,” the text reads, “I will be exalted among the heathen.”
This triumph of the Lord over all his enemies takes place not only at the end of time, but even now, as world history moves to that coming day. A mighty demonstration of the saving power of God is being constantly and currently unfolded, because amidst the rebellion and scorn of this unbelieving world, are bright lights like stars in the firmament.
These are believers resisting the flood of carnal inclinations, temptations and desires, and choosing, by the help of God, life and blessing. Repeatedly through each day they stop, restrain the alien thoughts, and prove the presence and help of Christ to govern the thought life.
And as God looks upon the earth, beholding all the arrogance and antagonism against himself, he is exalted by the lives that stand out, the people who are in communion with him, trusting and proving and praising him. By grace, they may be said to be conquering the devil and all his agents, putting down all their power and cunning, and proving the miracle of conversion.
Psalm 46 reveals to us its fullest significance when we see that it encompasses the thought lives and conduct of God’s people, proving the Lord in an alien world. The psalm begins: “God is our refuge and strength, a very present help in trouble.” How will the Lord provide his help? Answers the fourth verse—“There is a river, the streams whereof shall make glad the city of God.”
This unmatched river is the Word, and those people who order their thinking and their imagination to conform to its counsels are the shining stars in the firmament of history—for they are living demonstrations of God’s saving power and glory, and through them he is exalted.
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