In the condemnation of the Devil for tempting Eve, God said to Satan in Genesis 3:15, “ And I will put enmity between you and the woman, and between your seed and her seed; he shall bruise your head, and you shall bruise his heel.
The seed of Satan was in the fruit from the tree of the knowledge of good and evil.
Satan or Lucifer was a covering cherub in the garden of Eden. He was the most powerful and beautiful angel. With his presence in Eden he knew the garden well.
We do not know why the tree was in the garden to begin with or why it was used, but its effect was so negative on the DNA of man and woman that God regarded it as the seed of Satan.
In John 8:42-44, Jesus refers to the unbeliever as being of their father the devil.
42 Jesus said to them, “If God were your Father, you would love Me, for I proceeded forth and came from God; nor have I come of Myself, but He sent Me. 43 Why do you not understand My speech? Because you are not able to listen to My word. 44 You are of your father the devil, and the desires of your father you want to do. He was a murderer from the beginning, and does not stand in the truth, because there is no truth in him. When he speaks a lie, he speaks from his own resources, for he is a liar and the father of it.