The Friar agrees to marry Romeo and Juliet because he is a compassionate and caring individual who wants what is best for them. He knows that the young couple is deeply in love, and believes that their marriage will help to end the feud between the Montagues and Capulets. He also believes that Romeo and Juliet’s marriage will serve as a symbol of hope and peace for the warring families, which will help to bring about change in Verona. The Friar agrees to marry them in secret because he knows that their parents would never approve of their union. However, he believes that it is important for them to be able to follow their hearts without interference from others. The Friar knows that Romeo and Juliet’s love is true and pure, which makes him believe that their marriage will give them strength when dealing with challenges such as death or betrayal.