If I may...
This is just an outline. I can expound upon any point.
You will not find "non-believer" in the scriptures. There is only "unbeliever". The distinction is this: belief is a standard of behavior NOT simply a thought in the mind. All men know God is but, because of tradition, rebellion, carnality, etc. most men live as unbelievers... not living as if God is real.
This is like the word "disobedient" in the New Testament. The root of the word is the same word for apathy. We understand apathy to mean "uncaring or disinterested". To be "disobedient" is to ignore the reality of a standard being.
The key is this: human living assumes a standard of life. The standard for all men is Christ Jesus. Most men are unbelievers; men who do not live as if He is real even though they know He is real. In that reality disobedience is normal.
Last item: Adam had the spirit of God in him. This was the pneuma (nāp̄aḥ in the Hebrew) or the breath of God that was breathed into the lump of clay to bring him alive. Adam and Woman most certainly could have resisted the enemy in the garden.
Aaron, if i may ... a LOT of concepts in the Bible are not listed exactly word-for-word so if you say "where does it say in the Bible" that's the wrong question sometimes.
Because where does the Bible say the word "Trinity"? It doesn't. But we all (i hope) believe in the Holy Trinity.
I also agree with your other comments about disobedience and apathy. That's exactly my understanding too.
And unbelief, or rejection of God to be more accurate is a form of apathy.