• A taste of one's own medicine

• A taste of one's own medicine
-This phrase means that you are mistreated the same way you mistreat others. So when you give someone a taste of their own medicine, you are giving that person the same bad treatment that they have given to others.
You get “a taste of your own medicine” when you “taste” what it really feels like for someone else to have you act towards them the way you do.
: ‘A taste of your own medicine’는 남에게 안 좋게 한 만큼 그대로 당하는 것, 자기가 한 대로 받는 보복’이라는 뜻입니다.
e.g.)

I will give him a taste of his own medicine to teach a lesson.

 

 

<Context>
Mike: Hey did you see that person cutting in front of us in line just now?
Alicia: Yes I did. But don’t let it get to you. We’ll just have to brush it off and act like nothing happened.
Mike: No way, I’m not going to do that! It’s not fair. Let’s cut in from of him and give him a taste of his own medicine.
Alicia: It’s not a big deal and it’s not worth it.
Mike: Ugh! Fine.

Mike: 야, 저 사람이 방금 우리 새치기한 것 봤어?
Alicia: 응, 봤어. 신경쓰지마. 그냥 못 본척해.
Mike: 싫어. 저러면 안돼. 우리도 똑같이 새치기해서 우리가 당한 대로 되갚아 주자.
Alicia: 뭐 그런 일로 그러니. 그럴 필요 없어.
Mike: 아휴, 알겠어.


• taste one's own medicine
<Context> 친구가 항상 사람들을 놀리고 비웃는다면 이렇게 말할 수 있겠죠.
You should stop making fun of other people because you may soon taste your own medicine. 
네가 다른 사람들을 계속 놀리면 너도 똑같이 당해. 조심해.

Ref)
https://www.voakorea.com/learning-english/1876596
https://www.vanguardngr.com/2019/04/do-you-know-this-expression-a-taste-of-your-own-medicine/