.
The breath of life isn't limited to humans.
For example according to Gen 6:17, Gen 7:15, and Gen 7:22, every creature
aboard the ark with Noah, and every creature not aboard the ark, was
endowed with the breath of life.
If the breath of life were merely atmospheric gases, it would be possible to
revive a corpse with artificial respiration; so I think we have to conclude that
it's an energy vastly more powerful than anything found in nature.
It's my guess that the breath of life is what John the baptist was talking about
in Luke 3:8 when he said God is able to turn solid rock into sentient beings.
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