The words you say have the ability to direct your life; either to a sinful destiny or a godly destiny. I choose the latter, however, I often fail. I pray daily for help in this area and get sad when, once again, I blow it. James put it so well when he discusses this in the below passage. Readers were well acquainted with the understanding behind the examples of bits and horses, rudders and ships. They would have heard these analogies often. To compare those ideas with the tongue and the body makes one not think that you can control the body physically with the tongue but that the bit and the rudder controls the DIRECTION the horse and ship go, so similarly the tongue controls the direction a man goes; his is destiny to live a controlled, godly life.
“If we put bits into the mouths of horses so that they obey us, we guide their whole bodies as well. Look at the ships also: though they are so large and are driven by strong winds, they are guided by a very small rudder wherever the will of the pilot directs. So also the tongue is a small member, yet it boasts of great things. How great a forest is set ablaze by such a small fire! And the tongue is a fire, a world of unrighteousness. The tongue is set among our members, staining the whole body, setting on fire the entire course of life, and set on fire by hell. For every kind of beast and bird, of reptile and sea creature, can be tamed and has been tamed by mankind, but no human being can tame the tongue. It is a restless evil, full of deadly poison. With it we bless our Lord and Father, and with it we curse people who are made in the likeness of God. From the same mouth come blessing and cursing. My brothers, these things ought not to be so. Does a spring pour forth from the same opening both fresh and salt water? Can a fig tree, my brothers, bear olives, or a grapevine produce figs? Neither can a salt pond yield fresh water.” – James 3:3-12, ESV
How many times do we have to mess this up before we get it right? Probably until we are home with Jesus. However, it is not something that we should overlook. Actually, having the Holy Spirit dwell in you means that your words, if slanderous, used for gossip, cussing with friends because it is funny, or any other ungodly use should have a somewhat immediate effect on your own spirit. I’m not saying you will be perfect and never wrongly judge or criticize someone. I am also not saying that the occasional profanity won’t slip from your mouth by accident. The difference is that the moment it does, if you are truly walking in the Spirit, you will feel convicted. It won’t be months later or even weeks or days. It will be within a moment or two. Perhaps even an hour if you are really in a funk. But that conviction will weigh heavy on your heart. It will cause you to notice right away as a reminder to do better next time. If you are growing as a believer in Christ, you will notice growth. The more you are convicted and continue to walk in the Spirit, the better you will get at bridling your tongue.