Swami Mukundananda
What happens to me if I hold a grudge against someone who hurt me?
A grudge is like drinking poison
Holding on to ill feeling toward someone who wronged you is like drinking poison, because that ill will destroys your own inner being. The loss is ours.
Now if you tie it in a knot and keep it inside, thinking 'he did such a bad thing, he shouldn't have, he is a terrible man', then this feeling is like drinking poison.