The biblical canon, the apocrypha, history, and anthropology.
I would include mythology also, since most myths are based on some margin of truth. There are also paradigms that spell it out for you in plain sight, but I didn't include them as they under social and political incredulity (evermore than the bible canon.)
But, if you want to start with why Cain is NOT the son of Adam - assuming you see that
first born males are given literary priority in the bible canon (and
often in the Apocrypha,) and that you see Cain was alive when Seth was alive (especially since the Mark of Cain deterred the population of the planet from killing Cain.)
Genesis 4:17-24 gives the list of first-born males from Cain. Notice Cain does not have a "father" he came from.
Genesis 5 gives the list of first-born males per generation
that came from Adam - the first man.
You should also notice that Cain purposefully stole the prophetic names of Adam's future children for the purposes of polluting and confusing the generation from which the Christ would come.
The list of Cain's first born son's names are:
CAIN (POSSESSION) BEGOT:
Enoch - (The) Initiated/Dedicated
Irad - Fleet
Mehujael - (Smitten by God)
Methusael - Who is of God
Lamech - (and) Powerful
-- Jabal - (a) Stream of Water (Adah)
-- Jubal - (a) Stream (Adah)
-- Tubalcain - You will be brought of Cain (Zillah)
Hmm... "
An initiated/dedicated fleet (smitten by God,) who is of God, and powerful (like a stream of water) will be brought of under POSSESSION (CAIN) - will be dominated."
Is this not prophecy of the Enemy? Those "of God" are "the gods" - the father(s) of Cain and his offspring. Isn't counterfeit bloodline and people set on being THE people of God?
Even Christ Himself tried to clue us in on this campaign when He said that the pharisees and such were of their father the devil - or when he called them vipers. These are the same avatar entities, and the same class as dragons. It is in the very names of the generations.
Didn't God say that avatar snake would bruise the heel, but its head would be bruised (i.e. a kill shot)? When Christ resurrected by consequence of His perfection, He obliterated the "head of the campaign" designed to keep God's people as carnal, stimuli-focused, barely animated entities.
Now, let's look at the firstborns of Adam.
Adam (man/first man) gave birth to:
Seth - (an) Appointed
Enosh - Man
Kenan/Cainan - (with) Possession
Mahalaleel - (and) Praise of God
Jared - Descent
Enoch - Initiated/Dedicated
Methuselah - (as the) Man of the Dart (of sin)
Lamech - Powerful (, and)
Noah - (ending in) Rest
So, "(An) appointed man with possession(s) and praise(s) of God will descend, dedicated, as the Man of the Dart of sin: with power, ending with rest (of God.)"
There is enough information in the
canon alone to expose false prophecy, the enemy, and doctrine that divides and separates one from God.