I'm memorizing the book of Titus and just picked the project back up after about a month off. To be honest, I got spooked at the length of Titus 3:3. But I pushed through that verse and am now to Titus 3:5.
If you haven't recently read that sequence in Titus (3:3-5), do it. Slowly. Savor those words. Paul, in verse 3, acknowledged his ugly background: foolish, disobedience, deceived, enslaved. He lived in malice and envy, being hated and hating others.
Then, like an angel bursting through the clouds with triumphant trumpet shout, the kindness and love of God appeared, saving him. He wasn't saved by his own righteous acts but because of God's mercy.
God saved him by the washing of rebirth and regeneration of the Holy Spirit.
Paul was willing to sharply rebuke those who wandered from the truth but not because he reveled in his own superiority. He longed for others to know what he knew: only through God's mercy and kindness was he given new life.
That's good news. Go read it again!