My reading this morning took me to Psalm 51:15. The Psalm is the heart of the penitent King David.
In the previous verse David pleads for deliverance, a rescue, from the punishment due his sin.  His actions have brought death to his door and in true brokenness pleads for mercy with plain speech. Our writer promises to loose his tongue and praise God for this show of ultimate mercy.
Open thou my lips-for they are closed by fret
Often the saint swallowed by grief finds it difficult to speak let alone praise God for anything. Our lips must be loosed by the aid of God’s Spirit lest we are pitiful and silent. The hurt, though self inflicted, is deep.  The wound is open and now evident, exposed and ugly.  Grief is consuming and to continue in any relationship is challenging especially the most important relationships.  Shame has gripped this saint and like Elijah running from threat, the strongest desire is to find a cave and hide.
Still David seeks to have this overturned!  “Open thou my lips” is his prayer knowing God has been good and is due praise and thanks.
Open thou my lips-for they are clenched in fear
When David surrenders to the consciousness of his sin, fear captures him.  The fear that the previous twisted thinking that led him to his horrible season of evil might still be prevalent.  If so, what might he say? A perverted mind has no good words.  The fountain is spewing filth because the well is toxic!  Confession and contrition are not only good for the outward life but most critically for the inner man where life really happens.  The inner man is to be renewed day by day then the outward man is likely to follow suit.
Open thou my lips-for they are considerate of your favor
Has God been merciful? Can the king say God has been good? When we consider God’s goodness to us in the present it is a down payment on God’s favor in the future. God has never forgotten how to be good, kind, gracious, or full of mercy.  “It is of the LORD’S mercies that we are not consumed, because his compassions fail not.  They are new every morning: great is thy faithfulness”  Dear saint, If God has ever shown you kindness He can and will again.  If your Lord has favored you with grace He can again.   What God does today should create a consideration of what He can do in the future.  David has known God’s favor and requests a supernatural work to be done on his lips so that he might give God His due-Praise!
Are your lips closed?  Have you held back what is overdue toward your Father? 
Consider what may have closed off the channel of thanksgiving and praise. Sin, Selfishness, or the like?
Consider how long it has been since you sacrificed with your lips to God for His favor toward you.