[pa_dweller]

Not positive, but I suspect blu refers to

Gen. 9:6 Whoso sheddeth man's blood, by man shall his blood be shed: for in the image of God made he man.

[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]

Bingo!