[TXnMA]

I suppose one could even go back as early as Genesis 3:19, where, at the end of His curse laid upon on Adam for eating the forbidden fruit, God says,

"In the sweat of thy face shalt thou eat bread; till thou return unto the ground, for out of it wast thou taken; for dust thou art, and unto dust shall thou return."
(KJV)

To me that sounds like the curse of mortality -- the promise of certain death. I'm not sure where they find it, but some say that Adam was made to be eternal; and that with this curse, mankind's lifespans were cut short.

(I don't have the knowledge [or the research time today] to verify [or disprove] that proposition...)

OK, blu -- what do you think was the earliest imposition of the death sentence?

[blu]

After the flood, God established a covenant with Noah (this was after the whole "how long can you swim" thing!). God told Noah and his sons: "And surely your blood of your lives will I require; at the hand of every beast will I require it, and at the hand of man; at the hand of every man's brother will I require the life of man. Whoso sheddeth man's blood, by man shall his blood be shed; for in the image of God made he man. Gen 9:5-6

Translation: Everyone is going to die. Men who think they decided the how and when will die at the hands of others.

I don't know when the first instance of the death penalty was. I don't study the Bible (I'm Catholic, and it was well past my parochial school days when Bible study became popular), I came across this info while teaching our US Government (did you know that above the Chief Justice's seat in the Supreme Court the 10 Commandments are inscribed?) and World History.