“He abused me, he struck me,

he defeated me, he robbed me” –

in those who harbour thoughts like these

hatred will never be allayed.

For in this world hatred is never

allayed by further acts of hate.

It is allayed by non-hatred:

that is the fixed and ageless law.

Those others do not recognize

that here we should restrain ourselves.

But those wise ones who realize this

at once end all their enmity.

From the Majjhima Nikaya, 128 – The Middle Length Discourses of the Buddha.