The spiritual masters speak of the control of speech. Here are some thoughts on this.
1.) Better to be silent than to yap. Better to be silent even in good things than speak. This is an ancient rule. & Christ was before his judges. It is better to speak little than err by speaking a lot.
2.) Better to speak good about others rather than speaking ill howsoever true about your friend. When someone else speaks ill of your friend, either change the topic or say clearly that you won’t hear ill about your friend.
3.) Do not disclose the secrets of others. No matter what. You will not be respected even by the person to whom you spill the beans for telling another’s secret to her. If you betray the trust of one person, then you can betray the trust of anyone.
4.) Life is tough. Don’t make it harder for others by harping on the sorrows of life. Try to make it easier for other people.
5.) When angry, then definitely keep shut.