Euripides was writing during the beginning of the Dionysian invasion from the Near East, and so his play signals Dionysus's still incomplete integration into Greek religious and social life. Once Dionysus had been established as a legitimate god in the Greek pantheon, he became associated with civic forms such as theater, wine festivals, democracy and general revelry. But for Euripides, the relation between Dionysus and the established social order was still being contested. His play attempts to answer the question of whether there can be a space for the irrational within a well-structured and ordered space, either interior or exterior. The Bacchae depicts a struggle to the death between the twin forces of control (restraint) and freedom (release), and permits Dionysus to provide an answer to this question. The god's implicit message is that not only is there space within society for the irrational, but that such a space must be allowed for that society to exist and thrive. By denying or opposing the irrational, as Pentheus did, the person who opposes it, or the society that denies it, will be torn apart. The story of Pentheus and Thebes demonstrates the necessity of self-control, moderation, and wisdom in avoiding the twin extremes of the tyranny of order and the murderous frenzy of collective passion.
As the last work of his life, Euripides chose to write a play that discussed, among other themes, the origin and nature of his own art. The Bacchae deals with the different relationships of theater to various aspects of society, including its relationship to art itself. First, Euripides asserts the centrality of theater to Dionysian ritual. The rites alluded to in the play were replete with masked dancers, choral performances and processions of citizens in costumes. Dionysus, the god of the mask, offers his worshippers the freedom to be someone other than themselves, and in doing so, the chance to achieve a religious ecstasy through theater itself. Second, Euripides comments upon the relation of the individual self to the theater as spectacle and performance. In the beginning of the play, Pentheus is an external spectator and onlooker, gazing upon the bacchic rites with a removed, disapproving gaze. But when offered the chance by Dionysus, he moves from the margins to center stage of the drama himself. But Pentheus cannot navigate the dangers of the move, and loses control, losing himself to the role he wishes to play. He emasculates himself, loses his original identity as the rational sovereign, and exposes himself to the drama and its consequences—in his case, death. Third, Euripides wants to comment upon the play as an art form. He masterfully both draws the audience's attention to the artifice of the play, to its conventions and techniques, while at the same time asserting the seductive power of that very artifice, both over the characters in the play and over the audience itself.
One of the principal moral messages of the play extols the importance of maintaining fundamental balances in one's social and natural life, and Euripides demonstrates this principle in the structure and content of the The Bacchae. The play is sprinkled throughout with oppositions, doubles and pairings that can be organized into three categories. First, Euripides establishes a number of pairings between and even within characters: Dionysus takes two forms on stage, Pentheus serves as his double, and they switch roles in the course of the play. Cadmus and Tiresias are a pair, and the bacchic chorus and the mad women of Thebes provide a contrasting set. Second, there are formal dualities, including the chorus versus the main action of the drama, and the events recounted versus the events enacted. Third, thematic dualities feature strongly. The wild mountain is contrasted with the walled city, and the mortal denies—albeit futilely—the divine. Men face off against women, and the irrational does battle with the rational.
Euripides uses hunting as a central motif in the play, and it holds a defining place in several relationships, the roles of hunter and hunted shifting, or reversing, as the relationships change. First, Dionysus begins in the position of the hunted, the quarry of Pentheus and his men. Soon, the god inverts this relationship. Second, the chorus, in its odes, explicitly uses the hunting motif, identifying with the hunted Stranger early in the play, and as his position changes, so does their identification and imagery. This inversion is clearly demarcated in Interlude III. The Chorus first celebrates a fawn's escape from hunters as it races joyfully by the woods and river. But the free fawn changes into the divine hunter, returning for revenge upon his one-time pursuer: "the gods keep/ hidden in subtle ways/ the long foot of time, and/ hunt down the impious one." Third, Agaue returns to the palace, demented, boasting of her catch, which she refers to as "a fortunate quarry indeed." The instant she regains her senses, she stops using the word "hunt," and instead uses the word "murder"—demonstrating once again the fundamental danger contained within Dionysus.
Much of the tension and action of the play comes about due to two important disguises, that is, Dionysus disguised as the Stranger, and Pentheus as the female bacchant. The use of disguise was a comment on theater itself and its powers. More specifically, Pentheus's disguise resonates in other ways. Bacchic ritual often involved costumed enactments representing the death of an old self and the rebirth of a new self dedicated to the deity. Pentheus, not a willing devotee but an impious imposter, is literally killed after being dressed by Dionysus, with no possibility of being reborn into the cult. Pentheus's cross- dressing echoes the common Greek notion of the rite of passage, usually from boyhood to manhood and the position of warrior. In this sense, Pentheus's cross- dressing would have appeared to Ancient Greek audiences as a failed rite of passage, since he never realizes his transformation and induction into the cult.
Dionysus, in his human form as the Stranger, acts upon people, and in his divine form acts upon nature. These supernatural acts have two distinct modes, which reproduce the duality of his creativity and destructiveness. On the one hand, earthquakes, fires, and flashes of white light destroy the royal palace and wreak havoc. On the other, the maenads experience the positive side of his supernatural powers, receiving the gifts of the earth: wine, honey and milk issue forth from the ground for them.
Fawnskins are the key garb for bacchic ritual, described as "the sacred cloak." It is the first item mentioned by both the two old men and by Pentheus when they decide to dress as bacchants. The mountain dancers strive to emulate the speed and freedom of the fawn. In Greek lyric poetry, the fawn was the traditional symbol for playfulness. The fawn also plays into the hunting motif, central to the play, embodying the paradigmatic quarry. As the chorus sings in Interlude III: "Shall I in night-long dances ever set white foot in bacchis celebration, hurling my throat to the dewy air of heaven, like a fawn playing in the green pleasures of a meadow, when it has escaped the terrifying hunt."
In Greek visual art and the lyrical poetry of the time, Dionysus was commonly depicted as being graceful, with effeminate features and long, flowing hair. As Pentheus is both drawn to and disgusted by the bacchic revelry, so is he fascinated and revolted by the Stranger's looks, especially the Stranger's hair. He comments upon the hair several times, and when asked what he would do to his prisoner, his immediate response is: "first I shall cut off your delicate locks," to which Dionysus responds, "my long hair is sacred; I am growing it for the god." This exchange proves a revelation, for while the Stranger could have been growing his hair as a promise to a god, as was common practice, his hair is long simply because he is the god himself. When their roles are reversed and Pentheus is imprisoned by Dionysus, they mention hair first. At that point, hair symbolizes Pentheus's weakness or femininity, as Dionysus chides Pentheus: "But this curl has fallen out of its proper place, not as I fixed it under the snood well we whose care it is to look after you shall put it back in position; now hold your head straight." Dionysus's dominance over Pentheus is complete as he tucks the other man's hair into place in a moment not devoid of sexual overtones.
The bull is one of Dionysus's most common incarnations in Greek art and religious imagery. It expresses the god's power, leadership, virility, and his potency as a force of nature. The epithets used for him in cultic practice and in poetry often allude to his bullish form. Crucially, the shape of the god and his victim is sometimes the same, as in the case of the bull, often offered as a sacrifice in his honor. In the play, the maenads tear apart bulls in the frenzy of their sparagmos (the ritual dismemberment of animals) in the cowherd's speech. Pentheus, in particular, sees Dionysus in his bull-like form. When he thinks he is tying up the Stranger, he finds himself wrestling with a bull in the stables of the palace. Once he goes mad, he sees the Stranger as a bull.