Verses with the word rash in the Old Testament (2 verses):

Ecclesiastes 5:2
Be not rash with thy mouth, and let not thine heart be hasty to utter any thing before God: for God is in heaven, and thou upon earth: therefore let thy words be few.

Isaiah 32:4
The heart also of the rash shall understand knowledge, and the tongue of the stammerers shall be ready to speak plainly.