Snape is a complex character.He isnt evil,and at the same time,he isnt totally noble either.Snape is a grey character,with ALOT of weaknesses and foibles..Snape dislikes Harry ONLY because he is James Potter's son,and James and Sirius used to taunt and tease Snape amny years ago.This example I cited corroborates that Snape isnt a very noble man,but Snape isnt completely evil either.Snape protected Harry against Professor Quirrel's curse in The Philosopher's Stone,Snape gave Umbridge the wrong potion,and informed the Order of the Phoenix about Harry's being in danger in book 5.
Snape would have certainly wanted to avenge James Potter,because he HATED James and Sirius.We do not know anything about what EXACTLY Snape told Voldemort about the prophecy.As it is,Snape had heard only a part of it,and I strongly suspect it was Snape who tipped Voldemort about Harry Potter...Neville Longbottom too was born on the same day,but Snape perhaps saw to it that the Potters were destroyed as he intensely disliked them both.BUT,Snape not being THAT negative either he wouldnt have wanted Voldemort's nemesis to die,because then,there would be absolutely NO ONE to stop Voldemort,which meant he(snape) was forever going to be a slave of Voldemort,which I reckon Snape wasnt too interested in.As I said earlier,Snape perhaps worked hand in glove with Voldemort out of sheer fear,just as how all other Death Eaters too serve Voldy out of fear.So Snape,being selfish machinated a ploy,where James Potter(his arch enemy)dies,AND at the same time,he (Snape) gets freed from Voldemort's terror..Snape wanted to have the cake and eat it too😛..The ONLY way this would be possible was to somehow save Harry and destroy Voldemort.Snape isnt as powerful a wizard as Voldemort,so there was no way he could take on Voldemort single handedly...Snape thus devised a plan...MAYBE Snape knew how to retract the soul from a horcrux,which he did,and incorporated it into Harry..Which meant,when Voldemort took on Harry,he was attacking HIS OWN SELF,which rendered him completely powerless...I take back another of my earlier postulates,that Lily Potter's LOVE wasnt of any significance...It was LILY'S LOVE which SAVED HARRY...Repeating again,LILY SAVED HARRY,but she wasnt the reason why Voldemort was destroyed...Voldemort by attacking Harry,attacked himself,and was destroyed but the boy was protected by the magic of love,which saved him
As you said,there was no way that Voldemort would entrust Snape with his soul(my theory about Voldemort handing his soul to Snape is rather ludicrous,which doesnt hold any water 😆 )..
PS.I request you to use slightly bigger font,as its a bit laborious to read the small font😊
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