Compare and contrast Orestes and Medea. Both are characters in plays that deal with vengeance, but why is one character celebrated and the other...

This question refers to Orestes, the son of Agamemon and
Clytemnestra. After Agamemnon returned home from the Trojan War, Clytemnestra (aided by
her lover Aegisthus) killed Agamemnon. Later, Orestes took revenge and killed both
Aegisthus and Clytemnestra. In Book I of Homer's Odyssey, Orestes
is held up as a model of dutifulness for avenging his father's death. Later traditions,
however, are not quite as kind to Orestes as the questioner suggests. Orestes appears as
a character in Aeschylus' Libation Bearers and
Eumenides, Euripides' Electra,
Iphigenia at Tauris, and Orestes, as well as
Sophocles' Electra. In each of these plays, the tragedians raise
questions about the necessity and rightness of Orestes' killing of his mother.
Eventually, though, Orestes does escape "demonization." We should also keep in mind that
Orestes killed his mother in response to an oracle from Apollo, which commanded him to
kill her.

In contrast, the killings committed by Medea did
not have divine approval. Because Jason divorced Medea to marry King Creon's daughter,
Medea killed not only the princess (and Creon who is an inadvertent victim), but also
ends up killing her own children. Whereas killing one's mother is a horrific crime, a
mother killing innocent children is usually regarded as a more heinous crime. Also, from
the Greek perspective, the fact that Medea's killings were not sanctioned by the gods is
also a strike against Medea.