"All men are liars" cries out the Psalmist. And he's right - all except for One. There was One who spoke truth and spoke truth from the depths of His being, for He IS Truth. And when we enter into communion with Him, when He reaches us His life to be our life, then one of the things He relentlessly seeks to chase out of us is this propensity to lie. He takes away the perceived "need" to. I don't need to pretend to be better than I am; He has already kindly and freely regarded me as His child. Who do I have to impress? No one! I am baptized!
So the holy Apostle urges in Ephesians: "Therefore, having put away falsehood, let each one of you speak the truth with his neighbor, for we are members one of another." (4:25) And there we see the joy.
It is not just that the lying, spinning the tale to make ourselves look better than we darned well know we have the right to, is of the old self and needs to be left in Baptism's watery grave. The liar is letting something fill his mouth that displaces what God would have in that mouth: TRUTH. The truth about us is that we are liars. The truth about us is that God alone can free our tongues from the tangled webs we weave when first we practice to deceive. The truth is that God wants to fill our mouths with HIS Truth, with the praise and glorification of His Son, who is the Truth and who spoke only Truth and who would open our lips that our mouths might declare His praise. "Behold, You desire truth in the inward being." And so "Cleanse me with hyssop and I shall be clean; wash me and I shall be whiter than snow."
Only in the cleansing of the Lord can we congenital liars experience our needed deliverance; and glory to God in that cleansing there is hope for a new way of living! A way of living that speaks truth. Private confession is all about speaking the truth. But even more so is the word of truth I hear from my Confessor's lips: "I forgive you all your sins in the name of the Father and of the + Son and of the Holy Spirit." That's a truth pressed down on my head with his hands. And for it: Glory to You, O Lord! Glory to You!