If the truth is the Torah law, and the knowledge of good and evil is demonstrated in the torah law...why would eating from this tree that gave this knowledge, bring death upon mankind and not life?

As far as your interpretation of scripture regarding heaven and earth passing away when all is fulfilled, this could be interpreted differently if heaven and earth are meant to be symbolically and not literal.

Isaiah 24:1-5 –


“See, the Lord is going to lay waste the earth and devastate it; he will ruin its face and scatter its inhabitants...The earth will be completely laid waste...The earth is defiled by its people; they have disobeyed the laws, violated the statutes and broken the everlasting covenant.”
[NIV]


This passage is a prophecy of the coming attack and conquest by the Assyrians over the Jewish people. It should be obvious that the word EARTH is used as a symbol here, representing the place of the peoples or nation involved. The Assyrian army, used unwittingly as a tool of retribution by God, would come and destroy cities, and burn and loot the land, taking the people captive and killing many of them. The “inhabitants” of the earth would be “scattered” – that is, scattered abroad in captivity. If the earth is meant to be the literal globe, utterly devastated and made empty by God, then the scattered inhabitants would have been instant astronauts!


The EARTH, here, is a symbol of the promised land of Palestine that had become defiled due to the disobedience of God’s chosen people. They had violated the Law, and now they would reap the retribution of God.

ISAIAH 1:2 –


“Hear, 0 heavens! Listen, 0 earth!....”
[NIV]

This vision was to serve as a warning to the nation of Judah. It was not given to all of humanity, nor was it published or made known universally to all mankind. HEAVENS here refers to the religious and political authorities of Judah, and EARTH refers to the place and the people involved, and so to all the inhabitants of Judah.


ISAIAH 34:1-8 –


“...Hearken, ye people: let the earth hear....All the host of heaven shall be dissolved, and the heavens shall be rolled together as a scroll....For my sword shall be bathed in heaven: behold it shall come down upon Idumea, and upon the people of my curse, to judgment....For it is the day of the Lord’s vengeance.”

This passage is a prophecy of the destruction of Edom (Idumea), a prophecy so literally fulfilled that this land is barren and waste even today. The EARTH was the peoples of Edom, who were to hear this prophecy against them. God was angry with them and this was their warning of the coming destruction (“the day of the Lord’s vengeance”). This prophecy was not intended or designed to be heard and attended to by peoples of other lands.


The HEAVENS that would be “dissolved” and “rolled together” (like a discarded scroll of parchment), were the political/religious authorities of Edom – its government and armies and those who led that nation away from God’s path (v.2.). God’s bloody sword would be bathed in HEAVEN. The symbol is explained within that very passage in verse 5: “it shall come down upon Idumea.” God’s sword was not bloodied in God’s own heavenly spiritual realm, but rather in the “heaven” that was the worldly realm of the Edomite leaders.