1. “Of the devil” (1 John 3:8).
Since the old man is of the devil, the old man has the devil’s life and nature. When we live according to the old man, we are living according to the devil’s life and nature, so we are living out the devil’s life and manifesting his nature. When a person sins and does evil, he is living a devilish life and often manifesting a devilish appearance. Look at the people who are dancing in a dance hall, gambling in a gambling den, smoking opium in an opium parlor, or drinking wildly in a bar. Are they not living a devilish life? Do they not have a devilish appearance? When the Chinese refer to these evil habits, they call them “lifestyles of devilish confusion,” and they refer to the people involved in these evil habits as “little devils.” If a person does not have the lifestyle of a “little dancing devil” or a “little gambling devil,” he may have the lifestyle of a “little opium devil” or a “little wine devil.” Even a person who loses his temper looks like a little devil. If a person who is in the midst of a terrible fit of temper would look in a mirror, he would see that his appearance is devilish. People living by the old man spontaneously manifest a devilish appearance because their old man is constituted with the devilish life.
The Lord Jesus was incarnated in the likeness of a man, in the likeness of the flesh of sin, and in this likeness, He was crucified on the cross. This matter is typified in the Old Testament by the bronze serpent in Numbers 21. Whereas the serpent is the embodiment of the devil (Rev. 12:9), the bronze serpent had only the outward form of the devil, not his sinful content. Although the Lord was in the likeness of the flesh of sin (Rom. 8:3), He did not have the sin of the flesh. Instead, He was without sin (2 Cor. 5:21; Heb. 4:15). In contrast, the flesh of man is the issue of a mixture of the human life and nature and the devil’s life and nature. In God’s eyes man not only has the form of the devil, but his flesh is a mixture of the human life and nature with the devil’s sinful life and nature. With such a mixture, the old man is of the devil and has the devil’s life and nature. This is man’s true condition. The old man is a “devil-man.” The old man is evil and corrupted because the old man is of the devil and has the devil’s life and nature.
2. “According to...the spirit which is now operating in the sons of disobedience” (Eph. 2:2).
In this verse the word spirit refers to the aggregate of all the evil angelic authorities in the air, over whom Satan is the ruler. On the one hand, Satan is ruling in the air, controlling this dark world, and on the other hand, he is operating in man’s heart, causing man to follow him in disobeying God. Since he is personified in man as sin (Rom. 7:17), he easily and conveniently operates in man’s heart. Given this mixture of sin, the old man spontaneously follows Satan’s operation and obeys him. The thoughts, words, and actions of the old man all come from Satan’s operation in us and from our obedience to Satan’s operation in our heart related to our thinking, speaking, and doing. The old man obeys Satan because the old man is of Satan.
3. “In sin did my mother conceive me” (Psa. 51:5).
The old man was born of fallen Adam in whom there is sin. Consequently, the old man was conceived in sin and has a sinful nature. The old man not only contains the element of the devil’s life but also the element of sin. The old man commits sins because the old man is born in sin and is of sin, and since the old man is of sin and has the element of sin, he spontaneously sins. Whenever we live by the old man, we spontaneously commit sins. The old man cannot be separated from sin because the old man is of sin.
4. “The heart is deceitful above all things, / And it is incurable” (Jer. 17:9).
In this verse the word heart refers to the heart of the old man. The heart of the old man is deceitful above all things, and it is incurable. Deceitful above all things means that the heart is the most deceitful thing: Nothing is more deceitful than our heart. Incurable means that our heart is in the worst possible condition. It is incurable can be translated “it is exceedingly wicked.” This means that the heart of the old man is wicked to the extent that it cannot be cured. Since our heart is wicked to this extent, the old man is wicked to this extent, and since the heart is deceitful above all things, the old man is deceitful above all things. The old man is deceitful and evil because he has the devil’s life and nature with its element of sin. Since the devil is personified in the old man as sin and since the old man is conceived in sin, he is corrupt beyond compare.
5. “In me, that is, in my flesh, nothing good dwells” (Rom. 7:18; see also Mark 7:20-23).
In our flesh nothing good dwells. Nothing good dwells in our flesh since we are of the devil, conceived in sin, and incurably evil. Every sin that we commit comes from living by our flesh because our old man is full of sin. Even if we do not commit a particular sin, we still are inwardly full of sin because we have the flesh which is inwardly full of sin.
6. “Enmity against God; for it is not subject to the law of God, for neither can it be. And those who are in the flesh cannot please God” (Rom. 8:7-8).
These verses speak of our condition when we set our mind on the flesh. To set our mind on the flesh is to live by the flesh. In such a condition, there is enmity against God, and our mind is not subject to the law of God. In such a condition, it is not possible to be subject to the law of God even if we wanted to be subject to His law. Consequently, we cannot please God in our flesh. The flesh is of the devil, so it is enmity against God and not subject to the law of God. Furthermore, being conceived in sin, the flesh cannot be subject to the law of God. It is evil to the uttermost and full of sin, so it cannot please God. We must know the condition of the flesh. It is at enmity with God, it is not subject to God, it cannot be subject to God, and it cannot please God. If we have such a knowledge of the flesh, we will hate and reject it in order to not live by it.