The difference between a compliment and flattery is often motive. A compliment offers genuine appreciation for a quality or action seen in another person. The goal of flattery is usually self-advancement through gaining the favor of someone else. Compliments seek to encourage; flattery attempts to manipulate.
In Psalm 12, David lamented his society in which godly, faithful people had disappeared and been replaced by those who speak deceitfully “with flattering lips and a double heart” (v.2). They had said, “With our tongue we will prevail; our lips are our own; who is lord over us?” (v.4).
The question “Who owns my lips?” is a good one to ask ourselves when we’re tempted to use insincere praise to get what we want. If my lips are my own, I can say what I please. But if the Lord owns my lips, then my speech will mirror His words, which the psalmist described as “pure words, like silver tried in a furnace of earth, purified seven times” (v.6).
Perhaps a good way to show who owns our lips would be to begin each day with David’s prayer from another psalm: “Let the words of my mouth and the meditation of my heart be acceptable in Your sight, O Lord, my strength and my Redeemer” (Ps. 19:14).
He who guards his mouth preserves his life. - Proverbs 13:3 (RBC)