But the Egyptians knew about the second death when Abraham went down to Egypt and they were much afraid because of this, and this maybe the very reason why the Egyptians hated the Hebrews, because Hebrews were an abomination to the Egyptians. Abraham, who was a Hebrew, was not an abomination to the Egyptians when he first went down to Egypt but by the time they sent Abraham out of Egypt, he certainly was.
Then in the story of Abimelech, he certainly knew that he was destined for the second death because he had taken Sarah to become his wife, and he challenged God as to why he would die the second death when he had not actually done anything wrong.
Then in Ezekiel 18:19-32 we are told that God has no pleasure in anyone dying the second death for their sins. His desire is that mankind would repent of their sins and live rather than die the second death.
So, to turn your statement on its head, Jesus took an OT concept of the second death and told parables which further explained what God had meant in Gen 2:17.
The second death by no means is a spiritual death, but it does mean that those who go into the second death are separated from God.
Martha, certainly understood the concept of the second death when her brother, Lazarus died and was in the tomb for four days before Jesus came and raised him from the dead.
Daniel wrote in 12:1-3 the following: -
Daniel 12:1-3:- 12:1 "At that time Michael shall stand up,
The great prince who stands watch over the sons of your people;
And there shall be a time of trouble,
Such as never was since there was a nation,
Even to that time.
And at that time your people shall be delivered,
Every one who is found written in the book.
2 And many of those who sleep in the dust of the earth shall awake,
Some to everlasting life,
Some to shame and everlasting contempt.
3 Those who are wise shall shine
Like the brightness of the firmament,
And those who turn many to righteousness
Like the stars forever and ever.
where he wrote about the righteous being
resurrected to everlasting life and the unrighteous to shame and everlasting contempt by passing into the second death as punishment for their sins.
Your claims demonstrate a Darwinian evolutionary understanding of the development of mankind.
Shalom