I can believe the possibility of it "poisoning" the fruit somehow, but the day anyone shows the world a Serpent, Reptile or Amphibian that can actually talk to humans I will give up all I believe and follow the Bible blindly...I mean Faithfully.
If it was a metaphor, what for then, and why not...
Yes it is...even for non-believers...even if you just see it as a fallen Hero who died trying in his mother'r arms is a powerful image.
but the most powerful image is that of a good deed in action...it influences even the most heartless to participate without thought at times