THE RULING OF THE MIND
Every part of a believer’s being needs to be kept under control. The same is true with the mind. This should not be ignored even after the mind has been renewed. We must never allow our mind to be as free as it wishes. Otherwise, evil spirits will come and take it over again. We need to realize that our thoughts are the seeds of our conduct. If we are not careful in our thoughts, it will not be long before we fall into sin. After the seed of a thought has been planted, we do not know when it will grow, but sooner or later it will grow. If we carefully trace all the intentional or unintentional transgressions we have committed, we will always find that they were the fruit of previous thoughts. If we let a sinful thought remain in our head without getting rid of it, some time later, even years later, it will become a sinful act. For example, if we have a bad thought about a brother and do not remove it immediately, it will bear fruit, even though we know that it is wrong and have asked God for forgiveness! All improper thoughts will certainly produce improper conduct. Therefore, believers can ill-afford not to deal thoroughly with all their thoughts. If a person cannot keep his thoughts under control, he will find out that he is not able to control anything. This is why Peter said, "Girding up the loins of your mind" (1 Pet. 1:13). This means that we need to control our thoughts and not let them run wild.
God’s purpose is to bring "every thought unto the obedience of Christ" (2 Cor. 10:5). Therefore, believers should consider every one of their thoughts under the light of God. We should not allow any thought to run away from our jurisdiction or escape our attention. Every kind of thought has to go through our own examination and be under our own control.
While we are controlling our thoughts, we should make certain that no improper thoughts remain. All improper thoughts should be driven out.
A believer should not let his mind become lazy. This means that he has to apply his thoughts to everything. He should be a spiritual person with a full consciousness, not allowing his thoughts to remain stagnant or become loose. If he does, evil spirits will seize the opportunity for their work. His mind should not be lazy and without any work. It should always be active. Even after he receives a revelation in his spirit, he still should exercise his thought (mind). Do not think that after he has a revelation in his spirit he can act accordingly. He must apply his mind to examine and consider what he is about to do and find out if there is still any self-intention, anything not according to God, and anything that proceeds from the flesh. Is his behavior fully according to the spirit and fully according to God’s timing, or is there still something from the self? This kind of consideration will help the spirit to further brighten the revelation in the intuition. If it is not God’s revelation, it will be exposed. A mind centered on the self will prevent us from realizing God’s will. It is very helpful to disregard our thoughts that are centered on the self. God does not want us to follow blindly. He wants us to apprehend His will clearly. Anything which is not thoroughly apprehended is not reliable.
(Spiritual Man, The (3 volume set), Chapter 34, by Watchman Nee)