This is throughout the whole play. The theme of parental guidance develops over it. The act would be act 4 scene 2, and when The Friar yells at Romeo for being unthankful!
The Friar councils the young lovers but really makes a mess of things. His plan is dependent of all kinds of variables falling into place at the right time. He means well but not too bright in the planning department. He officiates the wedding of Romeo and Juliet, hoping to gain political peace through the union. When that doesn't work out, he concocts the plan to reunite the star-crossed lovers by giving Juliet a sleeping potion - but the plan backfires causing sorrow and death.
