What was the first unrighteous act of sin, the lie told by the devil by which Eve was deceived or the eating of the forbidden tree?
From Lucifer:
Ezekiel 28
By the abundance of your trading
You became filled with violence within,
And you sinned;
17 “Your heart was lifted up because of your beauty;
You corrupted your wisdom for the sake of your splendor;
Satan is the author of sin.
The first sin of Adam and Eve:
Starting to doubt if God was good and not loving Him with their whole heart, because they didn't really know Him. I think if they first ate from the Tree of Life, they wouldn't have sinned:
John 17:3
And
eternal life means to know you, the only true God, and to know Jesus Christ, whom you sent.
If Adam loved God with all his heart, he would have kept Eve from eating and have said: Let's listen to our loving Father instead of a talking snake. That way he would have loved her too. And Eve of course also didn't love God with all her heart or really know Him: guinosco: by experience.
Kids listen if you tell them not to take candy from a stranger, because they love and know you, even if they don't know (guinosco: by experience) that kind of sin.
Jesus, the second Adam didn't sin, because He knew and loved God the Father with all His heart.