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Evil thoughts are considered sins even if we don’t put them into action. Jesus said, “Ye have heard that it was said of them of old time, thou shalt not kill; and whosoever shall kill shall be in danger of the judgment: But I say unto you, that whosoever is angry with his brother without a cause shall be in danger of the judgment” (Matthew 5:21,22). And He also added, “Ye have heard that it was said by them of old time, thou shalt not commit adultery: but I say unto you, that whosoever looketh on a woman to lust after her hath committed adultery with her already in his heart” (Matthew 5:27,28).
In the Sermon on the Mount, Jesus showed that the attitudes of pride and arrogance and sinful thoughts, are considered sins because every sinful deed originates with a thought in your mind “For out of the heart proceed evil thoughts, murders, adulteries, fornications, thefts, false witness, blasphemies” ( Matthew 15:19; Mark 7:21).
The Lord wants us to renew our hearts and thoughts by the power of His Spirit “And be not conformed to this world: but be ye transformed by the renewing of your mind, that ye may prove what is that good, and acceptable, and perfect, will of God” (Romans 12:2; Joel 2:13).
Before conversion, man’s thoughts, the faculty for discerning between right and wrong, is under the dominion of bodily impulses. The mind is described as a “fleshly mind” (Col. 2:18). But at the time of conversion, the mind comes under the influence of the Spirit of God. The result is that “we have the mind of Christ” (1 Cor. 2:13–16).
In order to live right, our thoughts must be right. The development of Christian character requires right thinking. Therefore, Paul outlines a constructive program of mental activity. Instead of thinking about differences with others, or being anxious about daily needs, we should exercise our minds on positive virtues. He said, “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” (Philippians 4:8).
In His service,