As I reflect on certain times when as enabled by God's grace, I held my tongue, when I really believed that it would be better to leave certain words in my mouth and not in the ears of others I breathe a huge sigh of relief and thank God for enabling me to do something that I would have failed at without Him.
Thank God for the Holy Spirit who gives discretion as to when to speak and the grace as to how to speak and the power to withhold inflammatory words that cause great collateral damage. One does not have to apologize for the careless word not spoken, or for the defamation not inflicted upon another's reputation, no retractions, no rationalizations needed and no need to grieve over the loss caused by hateful words extinguished before launch.
Proverbs 17:28 Even fools are thought wise when they keep silent; with their mouths shut, they seem intelligent.