What role does Friar Laurence play in Romeo and Juliet?

Friar Laurence is presented as a holy man who is trusted and respected by the other characters in Romeo and Juliet. The Friar's role as the friend and advisor to Romeo and Juliet highlights the conflict between parents and their children within the play. The centrality of the Friar's role suggests a notable failure of parental love. Romeo and Juliet can't tell their parents of their love because of the quarrel between the two families.
In their isolation, Romeo and Juliet turn to the Friar, who can offer neutral advice. At first, the Friar can't believe how quickly Romeo has abandoned Rosaline and fallen in love with Juliet, so he reminds Romeo of the suddenness of his decisions. The Friar uses the formal language of rhyme and proverbs to stress the need for caution to Romeo. However, he agrees to marry Romeo and Juliet in the hope that their marriage will heal the rift between the Montagues and the Capulets. His decision to marry the lovers is well-meaning but indicates that he has been naive in his assessment of the feud and hasn't reflected on the implications of Romeo and Juliet's clandestine marriage.