lay down the law
Meaning: if you lay down the law, you tell people what they should do in a forceful and stern way.
- After a mafia player got the 3rd penalty, the moderator of the game laid down the law and said the player had to be careful or he’d be out of the game.
- Anna’s parents laid down the law after she got home late and grounded her for a month.
You can practice this idiom soon at one of the English Mafia Club’s upcoming meetings: https://englishmafiaclub.com/events/upcoming-events
See more English idioms and quotes here: https://englishmafiaclub.com/category/english-practice