Set a guard, O LORD, over my mouth; keep watch over the door of my lips! Do not let my heart incline to any evil. —Psalm 141:3-4
Words are a means to much sinning. “How great a forest is set a blaze by such a small fire! And the tongue is a fire, a world of unrighteousness… For every kind of beast and bird, of reptile and sea creature, can be tamed and has been tamed by mankind, but no human being can tame the tongue. It is a restless evil, full of deadly poison” (James 3:5-8).
So how do we suppress this plague of sinning with our lips? Moreover, how do we root it out? First we must understand that our lips are a doorway.
Our Lips Are a Doorway in Need of the Gate of God
Our minds and hearts are constantly busy with thoughts, judgments, intentions, ponderings, delights, hopes, musings, meditations, dreams, and strategies. Our lips are a doorway for the expression of these internal movements. We learn this not only from David in Psalm 141:3, but also from Jesus in Luke 6:45: “out of the abundance of the heart the mouth speaks.” The problem, as we have already seen, is that many of these internal movements are sinful and not God honoring. Our lips bear witness to the shameful reality of our sinful hearts. Moreover, our words don’t only reveal our sin but they multiply our sin. Our lips add an evil expression to the already existing evil intention.
Our first line of defense against a sinning tongue is to close the door of our lips. But the tongue is not easily tamed and the door of our lips is too heavy to shut on our own. We are desperate for God to shut the door for us. God must keep our words pure and supply us with the necessary self-control. This self-control is not self-generated, it is a gift from God. God is the great tongue tamer!
Our Hearts Have Inclinations in Need of the Guard of God
Praise God for the grace he gives in progressive sanctification. He shuts immoveable doors and tames untamable tongues. He fixes mouths so that the unkind or imprudent words are not given a voice!
But even if the doorway is shut and the darker intentions of our heart are not revealed by our lips, we are still defiled because the evil inclination of our heart still exists. Though it is mute, it is not dead.
Here we come against our greatest problem. If the door of our lips is immoveable and if our tongue is untamable, then the inclination of our heart cannot be shackled by even the strongest legion. Inclinations are not simple actions that can be modified or corrected. Inclinations are the natural impulse of our desire—a reflex that results from breathing. And we find that our inclinations are evil.
How can a heart inclined towards evil ever be changed? It is only by the grace of God that comes to us in Jesus Christ through the gospel. Through the work of the gospel, God not only tames tongues but he guides heart inclinations. He kills desires and gives new ones. He changes our natural impulse. He enlarges our heart so that we run in the way of his commandments (Psalm 119:32).