We have all gotten ourselves into trouble when we have unwittingly opened up our mouths and said something, we would later regret. Here is some wisdom from scripture about when to keep our mouths shut.
Keep your mouth shut if you do not have all the facts.
He that answereth a matter before he heareth it, it is folly and shame unto him. (Proverbs18:13)
Keep your mouth shut if it has not been verified.
The simple believeth every word: but the prudent man looketh well to his going. (Proverbs 14:15)
This is the third time I am coming to you. In the mouth of two or three witnesses shall every word be established. (I Corinthians 13:1)
Keep your mouth shut if you have not gone to the person first.
Moreover if thy brother shall trespass against thee, go and tell him his fault between thee and him alone: if he shall hear thee, thou hast gained thy brother. (Matthew 18:15)
Go not forth hastily to strive, lest thou know not what to do in the end thereof, when thy neighbour hath put thee to shame. Debate thy cause with thy neighbour himself; and discover not a secret to another: Lest he that heareth it put thee to shame, and thine infamy turn not away. (Proverbs 25:8-20)
Keep your mouth shut if it would damage another.
A froward man soweth strife: and a whisperer separateth chief friends. (Proverbs 16:28)
The words of a talebearer are as wounds, and they go down into the innermost parts of the belly. Burning lips and a wicked heart are like a potsherd covered with silver dross. He that hateth dissembleth with his lips, and layeth up deceit within him; When he speaketh fair, believe him not: for there are seven abominations in his heart. Whose hatred is covered by deceit, his wickedness shall be shewed before the whole congregation. Whoso diggeth a pit shall fall therein: and he that rolleth a stone, it will return upon him. A lying tongue hateth those that are afflicted by it; and a flattering mouth worketh ruin. (Proverbs 26:22-29)
Keep your mouth shut if the motive is revenge.
For even hereunto were ye called: because Christ also suffered for us, leaving us an example, that ye should follow his steps: Who did no sin, neither was guile found in his mouth: Who, when he was reviled, reviled not again; when he suffered, he threatened not; but committed himself to him that judgeth righteously: (I Peter 2:21-23)
Finally, be ye all of one mind, having compassion one of another, love as brethren, be pitiful, be courteous: Not rendering evil for evil, or railing for railing: but contrariwise blessing; knowing that ye are thereunto called, that ye should inherit a blessing. For he that will love life, and see good days, let him refrain his tongue from evil, and his lips that they speak no guile: Let him eschew evil, and do good; let him seek peace, and ensue it. (I Peter 3:8-11)
Keep your mouth shut if the only intention is to bring someone down.
A talebearer revealeth secrets: but he that is of a faithful spirit concealeth the matter. (Proverbs 11:13)
An ungodly man diggeth up evil: and in his lips there is as a burning fire. (Proverbs 16:27)
A froward man soweth strife: and a whisperer separateth chief friends. (Proverbs 16:28)
A wicked doer giveth heed to false lips; and a liar giveth ear to a naughty tongue. (Proverbs 17:4)