For we ourselves were once foolish, disobedient, led astray, slaves to various passions and pleasures, passing our days in malice and envy, hated by others and hating one another. But when the goodness and loving kindness of God our Savior appeared, he saved us, not because of works done by us in righteousness, but according to his own mercy--Titus 3:3-5a (ESV)
I. We do not save ourselves by our good works.
In Titus 3, Paul paints an almost hopeless picture of the unsaved sinner. His description applies to all of us. If youe a Christian like myself, it's a description of who we were and who we would be without God's salvation. If you're not a Christian, it describes you. Without God's grace, all we have is unrighteousness. Because of this, we deserve God's wrath for our sin. We need salvation.
The Gospel is the story of that salvation. "God our Savior appeared" and "He saved us." Listen to that again: He saved us. We aren't saved by ourselves or by our good works, but by God. So, the Gospel has no place for good works being our means of salvation.
II. God does not save us because of our goodness.
After convincing us that God saves us, not our works, Paul moves to God's motive for saving us. He answers the question, "Did He save us because he saw something good in us?" Absolutely not, Paul answers. "He saved us, not because of works done by us in righteousness, but according to his own mercy." God was not moved by our goodness to love us; He loved us while we were still evil. Romans 5:6 says "For while we were still weak, at the right time Christ died for the ungodly." God is not enticed to save us by our works. He sees our righteousness as the "polluted garments" that they are. (Is. 64:6)
We have nothing at all to do with our salvation. The only thing we bring to the Gospel is our sin.