Shakespeare uses light and dark imagery in this scene to describe the blossoming of Romeo and Juliet's romance. As Romeo stands in the shadows, he looks to the balcony and compares Juliet to the sun. He then asks the sun to rise and kill the envious moon. Romeo had always compared Rosaline to the moon, and now, his love for Juliet has outshone the moon. Thus, as Romeo steps from the moonlit darkness into the light from Juliet's balcony, he has left behind his melodramatic woes and moved toward a more genuine, mature understanding of love.
The scene takes place at nighttime, illustrating the way Romeo and Juliet's love exists in a world quite distinct from the violence of the feud. Throughout the play, their love flourishes at night — an allusion to the forbidden nature of their relationship. As night ends and dawn breaks, the two are forced to part to avoid being discovered by the Capulet kinsmen. Romeo and Juliet fear that they might be exposed — that the artificial light of discovery might be shone upon them, thereby forcing their permanent separation.
Shakespeare describes the natural quality of their love by juxtaposing the balcony scene with Mercutio's lewd sexual jokes in the previous scene. Romeo returns to the religious imagery used between the lovers in their sonnets at the feast when he describes Juliet as, "a bright angel" and "dear saint." The recurring use of religious imagery emphasizes the purity of Romeo and Juliet's love — as distinguished from the Nurse and Mercutio's understanding of love that is constituted in the physical, sexual aspects.
Romeo begins to display signs of increasing maturity in this scene. His speeches are now in blank verse rather than the rhymed iambic pentameter evident in his earlier sonnets and couplets. Romeo is no longer the melancholy lover of Act I. Up to this point, Romeo has expressed his emotions in a traditional, colloquial style. His behavior has been notably antisocial — he preferred to submit to the misery of his own amorous failures.
Although Romeo has matured in the brief time since the beginning of the play, he remains somewhat immature when compared with Juliet — a pattern that recurs throughout their relationship. Although Juliet is only 13, she considers the world with striking maturity. As later acts reveal, her parents do not provide an emotionally rich and stable environment, possibly forcing Juliet to mature beyond her years.
Juliet shows the beginnings of increasing self-possession and confidence that ultimately lead her to seek her own fate rather than a destiny imposed upon her by her parents. Juliet introduces the idea of marriage to Romeo. She makes the practical arrangements for sending a messenger to Romeo the next day. Juliet stops Romeo from swearing his love on the moon as it is too "inconstant" and "variable." She stops him from using traditional, colloquial poetic forms in expressing his affection. She encourages him to be genuine and to invest himself in a less traditional, more spiritual concept of love.
Juliet's soliloquy examines another of the play's themes — the importance of words and names. Juliet compares Romeo to a rose and reasons that if a rose were given another name, it would still be a rose in its essence. If Romeo abandoned his family name, he would still be Romeo. Juliet calls into the night for Romeo to "refuse thy name" and in return, she will "no longer be a Capulet." Therein lies one of the great conflicts of the play — the protagonists' family names operate against their love. While their love blossoms in oblivion to any barriers, the people who affect their lives use their familial battles to impose separation upon the two young lovers.
Juliet's promise to Romeo to "follow thee my lord throughout…