Through the fall of man the serpent injected himself into mankind. Where is this serpent now? He is in our flesh. In the garden, before the fall of man, the serpent was outside of man. However, since the fall, the subtle, crafty serpent is in man, in his flesh.
One day the Lord Jesus asked His disciples, "Who do you say that I am?" and Peter immediately responded, "You are the Christ, the Son of the living God" (Matt. 16:15-16). A short time after this the Lord rebuked Peter, calling him "Satan" (Matt. 16:23). Can you believe that one minute he was a holy Peter and that soon afterward he had become Satan? If I had been Andrew, Peter's brother, I would have asked the Lord Jesus, "Where is Satan? I am Andrew, and Peter is my brother, but where is Satan?" The Lord Jesus might have answered, "Satan is here within him. Satan is inside of Peter." When you speak in an evil way, who are you? You are Satan. When you act in a mean way with your wife or husband, who are you? Satan. At such a time the Lord Jesus could say of you, "Satan!" Where is Satan? He is within fallen mankind. Satan today is in man's flesh. We all must be on the alert because Satan, the one who tempted and damaged the first generation of mankind, is now within us.
Because Satan has injected himself into man, all men have become serpents in the eyes of God. Although you may consider yourself a man, in the eyes of God you are a serpent. According to Matthew 3:7, John the Baptist called the religious, Jewish people a "brood of vipers." They were serpents. John seemed to be saying to them, "You think of yourselves as religionists. You are so religious, yet you don't realize that you are a generation of vipers." In His explanation of the parable of the tares in Matthew 13, the Lord Jesus used the term "the sons of the wicked one" ("children" should be "sons," Gk.). Who is the wicked one? The serpent, Satan, the evil one—he is the wicked one and all his followers are his sons The followers of Satan are not his adopted sons they are his sons by birth. Thus, in John 8:44 the Lord Jesus said, "You are of your father the Devil." The Lord appeared to be saying, "Your father is the Devil because you have the Devil's life. The Devil's life and nature are in you. You were born of your father and now you have his life and nature." The Apostle John mentions "the children of the Devil" and says, "He that committeth sin is of the Devil" (1 John 3:10, 8). Therefore, Paul called Elymas the sorcerer the "son of the Devil" (Acts 13:10, Gk.). Even a gentleman such as Nicodemus, who appeared to be such an upper-class person, was a serpent in the eyes of God, possessing the serpentine nature. This is the reason that all the serpentine people need the Lord Jesus to be their substitute in the form of a serpent.
As children of the Devil, people who have been born of the serpent, we all have the serpentine nature and life (1 John 3:12). No one can deny or dispute this, since we see Satan's nature and life in our own children. Apparently little children are sweet; however, the more they grow, the more the serpentine nature within them is exposed. Although they are not trained to display the serpentine nature and life, they manifest it spontaneously. I have observed this in many children including my own. We must remember that we all are like that. Not only are we like that—we are that! We have a serpentine nature and life within us.