Let us pay attention to verses 17 and 18 which say that the nous of the Gentiles is corrupted by vanity, and the heart is hardened and alienated from the life of God. A Gentile is so corrupted that he has lost all feeling. But where does this corruption really begin? If we know where it begins, we can deal with that part first. Does the nous of a man become corrupted first? Does his life or heart become corrupted first? If we know what becomes corrupted first, we can deal with it accordingly. If the disease starts from the heart, we should deal with the heart first; if it starts from the nous, we should deal with the nous first; if it starts from life, we should deal with life first. Verses 17 and 18 show us the order of corruption for these three. The apostle told us not to walk in the vanity of the nous. (The vanity of the nous is like what the Chinese call "the palace in the sky" and Westerners call "the castle in the air.") We should not walk like the Gentiles walk because the function and thoughts of their nous are darkened. The function of the nous is darkened because the Gentiles are alienated from the life of God, and they are alienated from the life of God because they are ignorant and hardened in their heart. Therefore, the trouble starts from the heart. Because the heart is hardened, a person is alienated from the life of God, and because he is alienated from the life of God, the dianoia is darkened. Brothers and sisters, the cause of all diseases lies in the heart. I have often told the co-workers that it is not the head of a person that is improper, but the heart that is improper. People always think that man’s head is improper, but I say no, it is the heart that is improper.
Did not the last message say that man’s head rather than his heart is improper? Yes, but that was another matter. This matter concerns morality. If a man wants to be proper in his conduct, his heart must first be proper. Do you know why a Gentile will not believe in the Lord Jesus and has many arguments? Is it because we do not have enough reasons to convince him to believe in God or Christ? No, we have the reasons. Psalm 14:1 says, "The fool has said in his heart, there is no God." He will not believe because he has said in his heart that there is no God, not because he is incapable of believing. The Lord asked the Jews why they would not believe in Him and come to Him that they might have life. This is a problem of the heart, not a problem of the intellect. It is the heart that does not believe.
I can give some people who do not believe in God many reasons for the existence of God. They respond by saying that this sounds very reasonable. I can then tell them the reason that the Lord is the Savior. Again, they respond by saying that this sounds very reasonable. But this is not enough to make them believe. Man’s head is not improper; his heart is improper. Paul said, "If you...believe in your heart...you will be saved" (Rom. 10:9). The Lord Jesus also said, "Whoever...does not doubt in his heart....believe that you have received them, and you will have them" (Mark 11:23-24). The head is not the problem; it is not the issue. The heart is all that is needed to believe. The heart is our true "I," our person. This is why the Bible speaks of "an evil heart of unbelief" (Heb. 3:12), instead of "an evil head of unbelief." The heart, not the head, has been corrupted. This is why men will not believe and be saved. The heart has become improper. As a result, the nous has also become improper.
Not only are the Gentiles like this; even Christians are like this. Many Christians do not know God’s will; they are unwilling to obey God and do not understand the Bible at all. They are like this because their heart is sick. A bad nous is just the symptom; the cause of the bad nous is a bad heart. I am not saying that the nous is not sick; the main point I am emphasizing is that the heart is sick first. Therefore, the heart must first become right before the action of the nous can be corrected. It is useless to deal with the symptom; the only way to cure the trouble is to deal with the source.
(The Renewing of the Mind, Chapter 1, by Watchman Nee)