Of twisted thoughts

What should one do to someone who once trepassed you,
One who was once nasty or mean to you?
What would one do if one now has the chance,
To take revenge for that person's misgivings?

To make him pay for what he once did,
To make him recant what he once said,
To make sure he remembers how he once treated you,
To remind him that what goes around comes around?

Would you pay him back in his own coin,
And throw the book back at him,
Make his life miserable while you can,
Since you now have the power to do so?

Or would you forget what once was past,
Forgive his petty and beastly deeds,
Since it was almost eons ago,
That he once was mean to you?

What would you do?