My mouth has long been a problem of mine and something the Lord and I have been working on all this year. Especially at work...I really have a difficult time controlling my tongue there, lol. It's high stress and people get on my nerves alot there. I never leave the house anymore without getting on my knees and prayin a specific prayer for tongue control. And the Holy Spirit gives me warning each and every time a situation is getting ready to arise in which I want to open my mouth
and He wants me to be quiet
Try saying Psalm 19:14 aloud every day. It really helps me!
"may the words of my mouth and the meditation of my heart be pleasing to You, O Lord, my rock and my redeemer"