Such oracles are persuasive, don't you think? And even if I am not convinced, the rough work of the world is still to do. So many yearnings meet and urge me on (lines 297–299)
This passage comes at the end of Orestes's explanation for why he has returned again to Argos. Standing at Agamemnon's grave with Electra and the chorus, Orestes describes how Apollo sent an oracle commanding him to return home to avenge his father's death. If he should refuse, he would suffer horrible diseases and exile from every human community. His description is vivid and horrifying, enough to convince anyone to do the god's bidding.
However, Orestes explains that other reasons have motivated his return besides Apollo's threats. His sorrow for his father, his poverty, and his anger over Aigisthos's usurpation of his father's throne. This distinction between different motivations proves to be crucial at the climax of the play, when suddenly all of Orestes's resolve disappears just as he is about to kill Clytamnestra. While his personal reasons for seeking vengeance drive his actions through most of the play, it is Apollo's command that forces him to complete the deed. This is significant because it shows that while Orestes was willing to take personal responsibility for his matricide, his actual motivation at the moment of the murder comes from a divine source. Because Apollo was responsible for the actual crime being carried out, he will protect Orestes from the Furies when they come to claim their retribution in the Eumenides.
For word of hate let word of hate be said, cries Justice. Stroke for bloody stroke must be paid. The one who acts must suffer. Three generations long this law resounds. (lines 311–314)
The chorus says these words at the end of their first section in the kommos. They are the mouthpieces of the primitive law of retribution, which mandated that blood be paid for with blood. One who failed to avenge the murder of a kinsman was as guilty as if he had committed the crime himself. Justice demands that evil deeds be punished by further evil deeds. The chorus says these words in order to stir up hate and anger in Orestes and Electra. They insist that the old order of law must be respected, and that Agamemnon's murderers must pay for their crimes. While the chorus celebrates Orestes's intention to kill the killers, they show little awareness or concern for his fate after he has completed the act. They focus only on the immediate claims of Justice, which demand that Orestes turn murderer himself. It will be up to Apollo and Athena in the Eumenides to break this cycle of bloodshed.
They killed an honored man by cunning, so they die by cunning, caught in the same noose. (lines 556–558)
Orestes speaks these words as he begins to outline his plan for killing Aigisthos. It is significant that in laying out this plan, he makes no mention of what he intends to do about Clytamnestra. However, while he does not address it directly, he alludes to his intention to kill his mother in this quote, as he speaks of the killers in the plural form.
Orestes's statement pays homage to the old laws laid out by the chorus in the quote discussed previously. Although warriors in battle should confront their enemies directly, Clytamnestra and Aigisthos forfeited that right when they tricked Agamemnon into making himself vulnerable to murder. Thus, Orestes is justified in his approach to the confrontation.
This line is echoed again nearing the climax of the play, when Clytamnestra asks who is shouting up and down the halls, and the servant tells her that the dead are killing the living. Immediately recognizing that Orestes has plotted against her, Clytamnestra says, "By cunning we die, precisely as we killed" (line 888).
For a discussion of the 'noose', which can also mean 'snare' or 'net', see the Themes section of this SparkNote.
But you, when your turn in the action comes, be strong. When she cries 'Son!' cry out 'My father's son!' Go through with the murder—innocent at last. (lines 827–830)
The chorus speaks these words in their last ode before the climax of the play. After praying to Zeus, the household gods, Apollo and Hermes, the chorus addresses Orestes (figuratively, not literally.) Anticipating Clytamnestra's emotional hold over her son, the chorus warns him that when she appeals to him as a mother, he should deny his bond to her and call himself Agamemnon's son only. This way, he will not really be guilty of matricide, as Clytamnestra has been discredited as his mother. Since Clytamnestra has taken on the attributes of a man and violated the safety of the home, she no longer has a right to the privileges of a mother and deserves to die like a man.
This quote also reflects the chorus's naiveté regarding the outcome of Orestes's actions. They engage in the same kind of wishful thinking for which they criticized Orestes and Electra after the kommos. We will soon discover that the Furies do not consider Orestes to be innocent at all.
Wait, my son—no respect for this, my child? The breast you held, drowsing away the hours, soft gums tugging the milk that made you grow? (lines 896–898)
Clytamnestra says these words as Orestes is dragging her towards the body of Aigisthos in order to murder her alongside her lover. After taking on the attributes of a calculating man throughout the Agamemnon and calling for an axe to fight off Orestes, Clytamnestra here reverts to her maternal role in a last ditch attempt to fend off death. While there is a possibility that she is sincere in her wish to return to proper female norms, it is too late now to cross back into that territory. The audience is likely to have looked with disgust upon this emotional gesture, seeing it as a hypocritical act. Not only have we watched Clytamnestra forgoing her female role in favor of taking a strong male position over the household, but we have also learned from Cilissa that Clytamnestra did not, in fact, nurse Orestes at her breast as she claims. In defense of Clytamnestra, one could argue that Cilissa exaggerated her role in Orestes's upbringing in order to further stain Clytamnestra's reputation. However, the audience would have sided with Cilissa in this matter.
We can imagine that the chorus would have rejected this gesture entirely, as they have already told Orestes to consider himself to be Agamemnon's son only. Orestes, however, is deeply moved, and his resolve momentarily weakens. It is at this point that Pylades steps in to remind him of his pledge to Apollo, saying that it is better to make enemies of all men than to anger the gods. These words negate Clytamnestra's act and condemn her to death.