Electra and Orestes

Euripides: Orestes
Orestes defends himself to Tyndareus, his grandfather

             What else could I have done?
I had two duties, two clear choices,
both of them conflicting.

                My father begot me,
my mother gave me birth. She was the furrow
in which his seed was sown. But without the father,
there is no birth. That being so, I thought,
I ought to stand by him, the true agent
of my birth and being, rather than with her
who merely brought me up.

                                     And then your daughter -
I blush with shame to call that woman my mother -
in a mock marriage, in the private rites of lust,
took a lover in her bed. And I hurt myself
as much as I hurt her by that admission.
But I admit it: what does it matter now?

Yes, Aegisthus was her lover; he was the husband
hidden in the house. And so I killed them both,
two murders, both committed for the single motive
of avenging my father.