Ps. 34:11-14 Come, my children, and listen to me, and I will teach you to fear the LORD. Do any of you want to live a life that is long and good? Then watch your tongue! Keep your lips from telling lies! Turn away from evil and do good. Work hard at living in peace with others.
If you want to live a life that is long and good, then you have to watch your tongue. This does not mean you are guaranteed a long and good life, but it does mean that you will enhance your chances of living a messed up life that may be cut short if you don't watch your tongue. It has been said that honesty is the best policy, and it is true.
Lying to others makes you untrustworthy. If others cannot depend on you to be truthful, you will fail to have anyone in life who can depend on you in time of need. You will be lonely and without help in your own times of need.
A much better way to live is to turn away from evil and do good. When you live rightly with God, you can be trusted to tell the truth. God is truth and those who live in Christ will be a people of truth. A person that wants to please God will seek to be truthful in all things, even when it may not be convenient or when it may be costly for him to do so.
We need to work hard at living in peace with others. Truthfulness is absolutely essential for peaceful living. It doesn't come naturally or easily, but with a lot of effort it can be done. Our commitment to godliness enables us to not be at odds with others because of our untrustworthiness. Peace sometimes eludes us because of the heart issues of others, but as far as it is possible with you, live rightly with God so you can live rightly with others.
Notice that this is doable. We are told to take charge of our tongues, hearts, and living. If it were not possible, God would not tell us to do it.