The Friar tells them the entire plot of the play which we have just seen. It's sort of a recap.
Friar Lawrence married Romeo and Juliet in his cell.
He hopes that it will reconcile the feuding families. Which it does, eventually.
Friar Lawrence feels that a punishment is good when they are in harm and when Romeo is missing Juliet, that is a very good punishment.
Romeo, Juliet, and Friar Lawrence are in Friar Lawrence's cell.
Romeo goes to friar Lawrence about marrying Juliet
Friar Lawrence is referring to the act of uniting Romeo and Juliet in marriage. He believes that this act might help to end the feud between their families.
Friar Lawrence and Prince Escalus do not have direct interactions in "Romeo and Juliet." However, they both play significant roles in the story. Friar Lawrence tries to mediate and help Romeo and Juliet, while Prince Escalus acts as a figure of authority and tries to maintain peace in Verona. Both characters ultimately want to prevent further tragedy in the city.
Friar Lawrence hopes that the marriage between Romeo and Juliet can subdue the hatred between their two families, the Montagues and the Capulets. Friar Lawrence believes that the peace and love between Romeo and Juliet can influence the other members of the families.
It confirms the story that Friar Lawrence tells the families. It tells what has happened over the four days that only Romeo, Juliet, Nurse, and Friar Lawrence knew. About how Romeo and Juliet fell in love and married, etc.
Friar Lawrence tells everyone the truth including the Prince, but unfortunately doesn't do it until it is too late.
He feels that marrying them will stop the feud between their two families.
The Nurse and Friar Lawrence knew about it before anyone else because the Friar performed the marriage and the Nurse was Juliet's close confidant so she told her everything.