References to the idea of “jealousy” are very common in William Shakespeare’s play Othello and can be found easily by searching an online version of the text for the syllable “jeal.” A search for those letters at OpenSourceShakespeare.org, for instance, turned up twenty-one different examples.
Yet the idea of jealousy is important in the play even when it is not explicitly mentioned. Jealousy is perhaps the major theme of this work. Take, for example, the very first scene of the play – indeed, take the very first words. As the play opens, Roderigo’s jealousy of Othello for having won Desdemona is the immediate subject of discussion. Thus the theme of jealousy is announced at once.
Ironically, however, Iago pays almost no attention at first to Roderigo’s jealousy of Othello because Iago himself is jealous of Michael Cassio, whom Othello has appointed his lieutenant even though Iago wanted the position. Iago launches into a very long speech expressing his own jealousy of Cassio. He ends by complaining that Cassio
in good time, must his [that is, Othello’s] lieutenant be,
And I—God bless the mark!—his Moorship's ancient [that is, lower-ranking assistant].
Shakespeare could hardly have done more to emphasize that jealousy will be a central concern of this play. No sooner do Iago and Roderigo express their own jealousy, however, than they try to arouse jealous thoughts in Brabantio by telling him that Othello has stolen the affections of Brabanttio’s daughter, Desdemona. They thus try to ignite, in Brabantio, jealousy of Othello, who, by this point has become closely connected with the jealousy of all three men.
Significantly, when Iago in the next scene tries to arouse in Othello jealousy of Brabantio’s social power, Othello refuses to take the bait. Instead he seems confident of his own social position and background, and so we have or first indication that (at this point in the play at least) Othello is above jealousy. The fact that he is not jealous here will make his later descent into full-blown jealousy all the more shocking and tragic.
When Desdemona appears to explain her marriage to Othello, she does everything possible to express her love for the Moor without provoking jealousy in her father. Indeed, when it is proposed that she should stay at Brabantio’s house while Othello is away at war, she refuses:
. . . I would not there reside,
To put my father in impatient thoughts
By being in his eye. . . .
She does not, in other words, want to make her father jealous by being constantly before him. Brabantio, however, is more than willing to try to stoke jealousy in Othello, as when Brabantio says,
Look to her, Moor, if thou hast eyes to see:
She has deceived her father, and may thee.
Act I ends as it began, with both Roderigo and Iago giving vent to their jealousy. This time, however, Iago implies his own jealousy of Othello, not merely of Cassio:
. . . I hate the Moor:
And it is thought abroad, that 'twixt my sheets
He has done my office . . .
In other words, Iago is jealous of Othello partly because he suspects that Othello has had sex with Iago’s wife. The opening act of Othello, then, is shot through with the theme of jealousy, even though the actual word “jealousy” does not appear until twelve lines from the end of the act.