Hebrews 11:1-2
But we pay no regard to this, neither are we brought to our senses by what happened to the Pharisee. He said what was true, “I am not as this Publican”, he said it too in no man's hearing; yet was he condemned. If he were condemned when he said what was true, and uttered it in no man's hearing, what fearful [punishment] shall not they suffer, who like gossiping women, carry about everywhere lies which they do not even themselves believe? What shall they not endure?
8. Henceforward let us set “a door and a bolt before the mouth.” For innumerable evils have arisen from tattling; families have been ruined, friendships torn asunder, innumerable other miseries have happened. Busy not yourself, O man, about the affairs of your neighbor.
But you are talkative and hast a weakness. Talk of your own [faults] to God: thus the weakness will be no longer a weakness, but an advantage. Talk of your own [faults] to your friends, those who are thorough friends and righteous men, and in whom you have confidence, that so they may pray for your sins. If you speak of the [sins] of others, you are nowise profited, neither have you gained anything, but hast ruined yourself. If you confess your own [sins] to the Lord, you have great reward: for one says, “I said, I will confess against myself mine iniquity to the Lord, and Thou forgavest the impiety of my heart.”
Do you wish to judge? Judge your own [sins]. No one will accuse you, if you condemn yourself: but he will accuse if you do not condemn; he will accuse you, unless thou convict yourself; will accuse you of insensibility. You have seen such an one angry, irritated, doing something else out of place? Think at once, even thou on your own [faults]: and thus you will not greatly condemn him, and wilt free yourself from the load of your past transgressions. If we thus regulate our own conduct, if we thus manage our own life, if we condemn ourselves, we shall probably not commit many sins, and we shall do many good things, being fair and moderate; and shall enjoy all the promises to them that love God: to which may all attain, by the grace and lovingkindness of our Lord Jesus Christ, with whom to the Father together with the Holy Ghost, be glory, power, honor, now and for ever and world with end. Amen.
Source: Homilies on the Epistle to the Hebrews (New Advent)