Binding Oaths

I have a fun little magic item that I throw in time to time called the “Magic Contract” it literally just magically forces them to comply in any way. I do t use it all the time, but sometimes I do if they’re dealing with a powerful being (e.g. Fey, Gods, Demons, powerful sorcerers, etc)

Quote from Pantagruel666 >>

I have an event in my game where participants are required to swear an oath to, basically, be good guests (no fighting except in a mutually agreed on dueling area, no other types of hostile behavior, let people arrive and leave freely and safely, etc). While many participants would be expected to honor such an oath without specific enforcement, others would not.

Is there a spell or creature power that does this? I can invent something, but if there's an existing model it would be nice. There are devils involved so some weak form of an infernal contract is an option.

 I wanted to make sure you saw this in drops. 

https://www.dndbeyond.com/spells/3368629-pinky-swear