My desires, like fell and cruel hounds / E’er since pursue me (1.1.)

Orsino describes how he fell in love with Olivia. He compares himself to a deer being hunted by hounds to describe how painful and stressful he finds it to love a woman who does not seem to reciprocate his feelings. The line shows Orsino’s tendency to be melodramatic and focus on himself. Even though he barely knows Olivia and she has told him she is not interested, he persists in feeling like his life depends on their relationship.

I have unclasped / To thee the book even of my secret soul (1.4.)

Orsino tells Viola, disguised as Cesario, that he has shared all his secrets with the younger man. Viola’s masculine disguise allows her to develop an emotional intimacy with Orsino that would not have been possible in a time when men and women were not usually allowed to spend much time alone together. Even though Orsino believes he is interacting with Cesario as a male friend, he is deeply drawn to him, which foreshadows the way he will realize he loves Viola when her true identity is revealed.

I know thy constellation is right apt / For this affair (1.4.)

Orsino explain to Viola/Cesario why she is the right person to woo Olivia on his behalf. The quote is ironic because Orsino knows that there is something special about Cesario, but he misunderstands what it is. Orsino does not realize that Cesario’s good looks and gentle manners come from him being a woman in disguise. The quote is also significant because it sets up the conflict that will later occur: Orsino assumes that Cesario’s charms will make it more likely for Olivia to change her mind, but instead she falls in love with Cesario himself.

Our fancies are more giddy and unfirm /More longing, wavering, sooner lost and worn / Than women’s are (2.4.)

Orsino muses on the differences between men’s and women’s feelings without knowing that he is talking to a woman, and to a woman who is in fact in love with him. Orsino reflects that he thinks men’s feelings are changeable and unreliable. This quote foreshadows the way Orsino will abruptly forget his feelings for Olivia and declare his love for Viola at the conclusion of the play.

I’ll sacrifice the lamb that I do love / To spite a raven’s heart within a dove (5.1.)

Orsino is angry and jealous to learn that Olivia is in love with Cesario, and threatens to harm or perhaps even kill Cesario as a kind of revenge. Orsino admits that he himself is very fond of Cesario, but it is more important that he have his revenge against Olivia. He accuses Olivia of being cruel and spiteful despite her beautiful appearance, comparing her to a raven hidden inside the appearance of a dove.

Farewell, and take her; but direct thy feet / Where thou and I henceforth may never meet (5.1.)

Orsino reacts to the news that Cesario and Olivia have apparently been married (it is, of course, actually Sebastian who married Olivia). At this point, Orsino is so hurt and betrayed that he stops being angry and becomes sad and resigned. He accepts the marriage, but banishes the couple so that he does not have to see them. Orsino has been very fond of Cesario and feels hurt that his friend would secretly betray him.

One face, one voice, one habit, and two persons! (5.1.)

Orsino is amazed to see Sebastian and Viola (in disguise) next to each other. He realizes that the two are basically identical, and that their similarity must be the source of all the confusion. The scene functions as the climax of the play, and the moment when all of the misunderstandings start to make sense.