Thank you for the question on Cain, “Is Cain (from the Bible) still alive and roaming the earth? (If you have a long answer, please tl;Dr)”,
The short answer is that Cain, the son of Adam, is dead. Although the Scripture does not state that Cain died, the result of Adam and Eve’s sin of eating the forbidden fruit led to their eventual death including Cain. The only way that Cain could have remained alive was to eat from the Tree of Life. Since an angel guarded the Tree of Life from Adam and Eve as well as their descendants from eating the fruit of that tree, then all of Adam and Eve’s descendant died.
Genesis 3 says this, “24 After he drove the man out, he placed on the east side of the Garden of Eden cherubim and a flaming sword flashing back and forth to guard the way to the tree of life” (NIV).
Genesis 4 says this, “16 So Cain went out from the LORD’s presence and lived in the land of Nod, east of Eden” (NIV). Cain did not have access to the fruit from the Tree of Life so he died a natural death, through a wild beast or from another man.
SUMMARY: Cain died just like Adam and Eve died.
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