Let Mouth Write a Check, Your Ass Can't Cash

My grandfather used to tell me all the time not to let my mouth write a check that my ass would not be able to cash.  Basically he was reminding me to be careful what I said because of potential consequences.  There was a recent incident at my job where such an event occurred.  Someone decided to write a big check with their mouth.  Actually, they wrote the check and then tried to change the value of the check.  In the end, the check was completely voided.  Her ass could not cash that check and the consequences of her actions surpassed anything that anyone there expected.