Orestes makes a prayer to Zeus, speaking for both himself and Electra, asking the god to watch over them like a brood of young eagles whose father died in a snake's coils. Both children are now miserable exiles. Orestes reminds Zeus in his prayer that Agamemnon always made good sacrifices to the gods. If he and Electra were to die, who else would pay him homage with such rich feasts? He pleads with Zeus to tend to the root of the house, so that it may flourish again and serve him.
The leader of the chorus interrupts Orestes's prayer and reminds the children to speak softly, lest someone should hear and report them to 'the masters'. The leader wishes she could see them covered with pitch and burning alive.
Orestes continues his speech, now telling how Apollo will never fail him. He says that Apollo spoke to him, warning that if he did not hunt down his father's murderers, he would suffer immense pain. The unappeased dead "take root beneath the soil" and plague the lives of men. One who failed to avenge the death of his kin would be covered in leprous boils and a cancerous skin. The Furies would pursue him with burning eyes, pleading for revenge. Such a man will wander as an exile, polluted by death and unable to approach any alter. He would be a pariah, reviled till death.
Orestes finds such oracles persuasive, but, even if Apollo could not persuade him, he would still have the drive to avenge his father's death. Other impulses come to play, like sorrow for his father's death and the poverty he must undergo as an exiled prince. He also hates how his countrymen, who fought so bravely at Troy, should be ruled by "two women", i.e., Clytamnestra and Aigisthos. Or, Orestes says, if Aigisthos is not weak like a woman, then he will soon get the chance to prove it.
Orestes's opposition of snake and eagle imagery is highly significant in the context of the Oresteia. The eagle is the sign of Zeus, which explains why Orestes compares himself and Electra to an eagles' brood. Zeus and Agamemnon are both key father figures in this play, and they are conflated into one eagle image. Clytamnestra, on the other hand, is a conniving snake. When Orestes says that the eagle has died in her coils, he does not mean by strangulation. Rather, female vipers were thought by the Greeks to bite the neck of the male while mating. Viper babies, in vengeance, killed their mothers by biting their way out of her womb (this belief is attested in Herodotus's Histories, 3.109.)
The analogy is thus extremely apt in this situation, as Clytamnestra's children will be the death of her. We will also soon see how Orestes compares himself to a snake. The coils of the snake twisting about her mate also echo the metaphorical net of persuasion that Electra claims Orestes is winding about her at first. It is also interesting to note that Electra and Orestes are metaphorically represented as both eagles and snakes in this passage.
Orestes does not simply ask Zeus for pity. According to Orestes, it is in Zeus's best interest to help him and Electra, for they will be able to make rich sacrifices to him in return. It was common in Greek prayer for the petitioner to remind the god of past sacrifices and to make promises of large sacrifices in the future. This idea of buying a god's favor might seem strange to us, but it was customary to the Greeks, who did not see their gods as benevolent deities. Rather, they thought of them as extremely powerful and fickle beings whose favor had to be curried in order to avoid malicious punishment.
In the second half of his speech, Orestes reveals that Apollo is the source of his confidence. It was Apollo who spoke to him in an oracle and warned him of the horrific tortures that would befall him if he did not avenge Agamemnon's death. The Furies pursue men who do not avenge their kin's death. For, failing to avenge a death was equivalent to causing it. Apollo's association with the Furies here shows that the cthonic and Olympian powers are still aligned. It is not until the Eumenides that a conflict between these two groups of gods erupts.
One who does not avenge a kinsman's death must suffer from the plague, which is an outward manifestation of the inward pollution associated with this act. The Furies mark those who do not carry out their commands so that no society will accept them. Orestes laments that "for such as us, no share in the wine-bowl, no libations poured in love." He refers to the custom that prohibits those who are polluted by blood from taking part in sacrifices. No one could take part in a religious rite without being absolved of blood that he had shed.
The last part of Orestes's speech (beginning with line 297) shows us that Apollo is not the only motivating factor in his quest for revenge. Even if Apollo had not convinced him, his own desires push him towards this goal. This separation of impulses will become far more significant at the climax of the play, when Orestes hesitates to kill Clytamnestra. In the end, it is the god's command and not his personal hatred that forces him to do the deed. These personal desires, however, will now take the center stage in the "kommos" section of the play that follow Orestes's speech.