We can use our words for harm. I have promise people things but I didn't act upon it. I know we have all done that. It makes you feel bad so the Bible warns against this.
1My son, if you have put up security for your neighbor,
if you have shaken hands in pledge for a stranger,
2 you have been trapped by what you said,
ensnared by the words of your mouth.
3 So do this, my son, to free yourself,
since you have fallen into your neighbor’s hands:
Go—to the point of exhaustion—
and give your neighbor no rest!
Now if you have done this; therefore, we need do this. We need to ask for forgiveness to God to the people. So we need to be careful with our words.
4 Allow no sleep to your eyes,
no slumber to your eyelids.
5 Free yourself, like a gazelle from the hand of the hunter,
like a bird from the snare of the fowler.