Using Aristotelian analysis, the chorus would be classified as a "character" that is like us. Compared to Antigone, the chorus plays much less of a participative role in the plot of the play. Instead, as the chorus speaks, it seems to be observing the events that are unfolding and commenting on them.
Towards the beginning of play, we, the audience, are presented with the fact that Medea has been abandoned by her husband Jason. The reason Medea is abandoned is simply because Jason has the opportunity to marry a Princess. Medea has done nothing wrong herself. Looking upon the situation, it is quite likely that the audience would feel sympathetic towards Medea's grief. The chorus makes its sympathy for Medea quite clear. The chorus states "I do grieve, lady, for the sorrows of this house, for it hath won my love."
As Medea is still grieving the fact that Jason has left her, Creon comes to tell her that she will be exiled. Once again, the chorus expresses its feelings, very typical of how an audience would feel toward a woman who has been abandoned by her husband only to be exiled by her King. The chorus states "Ah! poor lady, woe is thee! Alas, for thy sorrows! Whither wilt thou turn? What protection, what home or country to save thee from thy troubles wilt thou find? O Medea, in what a hopeless sea of misery heaven hath plunged thee!"
As the play continues, however, Medea makes it clear that she wishes to kill her children in an effort to get even with Jason. While these children have played no fault in Jason's abandonment of Medea, a reaction from the audience would most likely be repulsion from a mother's murder of her own children. The chorus, feeling as we would, states it views on Medea's plan by stating "’Think on the murder of thy children, consider the bloody deed thou takest on thee. Nay, by thy knees we, one and all, implore thee, slay not thy babes." The chorus additionally states "Where shall hand or heart find hardihood enough in wreaking such a fearsome deed upon thy sons? How wilt thou look upon thy babes, and still without a tear retain thy bloody purpose? Thou canst not, when they fall at thy feet for mercy, steel thy heart and dip in their blood thy hand."