Friar Laurence and Romeo wait for Juliet. Romeo is so excited he says that no matter what sorrow might come, it cannot compare to his joy. The Friar counsels moderation in everything, including love, saying "These violent delights have violent ends" (2.5.9).
Contrast between Romeo's passions and the Friar's moderation. And the Friar is right: Romeo's end is violent. But Romeo wouldn't have it any other way.
Juliet arrives, and Romeo asks her to describe her love for him. But Juliet refuses. She comments that "They are but beggars that can count their worth" (2.5.32). She says her love is too large to describe.
Juliet calls Romeo on his overly-poetic love. She makes him see that love is bigger than just saying the words.