Because the moon is inconstant and ever changing, and Juliet wants to know that Romeo will love her forever.
She doesn't want him to swear his love by the moon lest "that thy love prove likewise variable". Juliet is afraid that if he does then his love will be changing as the moon (inconstant orb) does.
Well, she says that since the moon changes constantly every month, it is not a good image for a faithful love. But in reality, she is speaking about the custom of young men in Shakespeare's day to swear their love up and down by anything they could find, as a means to persuade the young woman (who by the same custom is supposed to be aloof and hard-to-get) to yeild to him.
Shakespeare sneers at this custom in Hamlet with this exchange:
Oph: And hath given countenance to his speech, my lord,
With almost all the holy vows of heaven.
Pol: Ay, springes to catch woodcocks.
In Romeo and Juliet, Juliet has been surprised speaking her own mind, and cannot now play the artificial "I am cold, aloof and strange" game. Since she must be honest and direct, she wants Romeo to be the same, so she tells him "Do not swear at all."
because moon always changes , so she doesn't want Romeos feelings according to Juliet to change like moon. she wants him to love her forever
Because the moon comes and goes, which is a bad thing to compare your love to.
The moon changes from new moon to full moon and back again every month. Juliet thinks that if Romeo swears by the changing moon, his love will prove just as fickle and changeable.
The Moon Changes
because the moon is always changing
I think this is referring to this bit of dialogue: Romeo: Lady, by yonder blessed moon I swear... Juliet: O, swear not by the moon [ ... ] lest thy love prove likewise variable. In other words, she's not telling him not to swear his love, she's telling him "Don't swear on the moon. It changes. I don't want a love that waxes and wanes." If you meant something else, please be more specific.
Because the moon is inconstant and ever changing, and Juliet wants to know that Romeo will love her forever.
not to swear at all ....actually first she askes him to swear by himself...then not to swear at all It's the other way around. "Do not swear at all; Or if thou wilt, swear by thy gracious self, Which is the god of my idolatry, And I'll believe thee."
she objects to his swear apon the moon because the moon changes and becomes dark and she doesn't want him leaving her
"Oh, swear not by the moon, th'inconstant moon that monthly changes in her circled orb, lest that thy love prove likewise variable" This is a personification; the monthly change in illumination is likened to the changing moods of a person. Juliet does not want him to swear by anything that is so untrustworthy.
I think this is referring to this bit of dialogue: Romeo: Lady, by yonder blessed moon I swear... Juliet: O, swear not by the moon [ ... ] lest thy love prove likewise variable. In other words, she's not telling him not to swear his love, she's telling him "Don't swear on the moon. It changes. I don't want a love that waxes and wanes." If you meant something else, please be more specific.
Because the moon is inconstant and ever changing, and Juliet wants to know that Romeo will love her forever.
He wants to swear by the moon, but Juliet doesn't want to hear him swear by the moon.
"By yonder blessed moon I swear--" But she doesn't like that very much.
not to swear at all ....actually first she askes him to swear by himself...then not to swear at all It's the other way around. "Do not swear at all; Or if thou wilt, swear by thy gracious self, Which is the god of my idolatry, And I'll believe thee."
she objects to his swear apon the moon because the moon changes and becomes dark and she doesn't want him leaving her
"Oh, swear not by the moon, th'inconstant moon that monthly changes in her circled orb, lest that thy love prove likewise variable" This is a personification; the monthly change in illumination is likened to the changing moods of a person. Juliet does not want him to swear by anything that is so untrustworthy.
He tried swearing by the moon. This didn't cut much with Juliet, who said "Swear not by the moon!"
Juliet does not want Romeo to swear by the moon because the moon is constantly changing and she fears his love will also change like the moon. Juliet wants Romeo's love to be constant and unwavering, not subject to the shifting phases of the moon.
ROMEO AND JULIET, Act 2, Scene 2
because the moon is always changing
Romeo wants the sun to kill the envious moon because he believes the moon is a symbol of unattainable love and beauty due to the moon's ever-changing nature. By having the sun kill the moon, Romeo is expressing his desire to rid himself of obstacles preventing him from being with his love, Juliet.