13 Keep [natsar] thy tongue [lashown] from evil [ra`], and thy
lips [saphah] from speaking [dabar] guile [mirmah]. KJV-Interlinear
your tongue from evil and your lips from speaking deceit. ESV
Evil is the policy of Satan. Truth is the policy of God. Deceit is the method of Satan. Grace is the method of God.
Both evil and deceit go hand in hand, for they require one another in order to be of any effect. And, both evil and deceit are only effective on the naïve, or those who do not recognize them. The objective of evil and deceit is never good or for the betterment of ones life, but are the design of destruction and failure and ruin.
Truth and grace operate for the betterment of everyone, regardless of whether you know of them or not. Truth and grace serve good and seek only that which is the best for anyone and everyone. The objective of truth and grace is for the completion and success of ones life, forever.
You have heard the phrase, ‘If you have nothing good to say, then do not speak.’
And that certainly applies here. For anyone who has nothing good to say, is not interested in making ones life better, but is interested in making ones life miserable.
Constructive criticism is not speaking bad things when the advice is indeed constructive with the objective of helping.
But criticism, complaining, sarcasm, mockery, gossip, maligning and so forth that are intended to bring harm or hurt, are not constructive, but examples of evil.
Therefore, do not let yourself be a servant of evil or deceit. Their origins are of Satan.
Know what you are talking about, before you speak. And learn so that you will know what is truth, and what is not.