The tongue is among the smallest members of the body and it can do much good but it can also be deadly.
Life & Death in the Tongue
Have you ever said something you regretted? I know I have and I’m sure we all have. Sadly, we can’t take our words back. Once they’re out of our mouth, they’re free to do their damage, so we must put a check on our words, and think before we speak. There is life and death in the tongue. It can bring life or it can bring death. James said “the tongue is a small member, yet it boasts of great things. How great a forest is set ablaze by such a small fire” (James 3:5). With all the wildfires we’ve seen, we know that only a tiny spark can cause a huge forest fire…and so it is with the tongue. One tiny word can spark a war, ruin a relationship, and get someone fired from their job. That’s why Solomon wrote that “Death and life are in the power of the tongue, and those who love it will eat its fruits” (Prov 18:21). 
Bridling the Tongue
I’ve ridden horses almost all my life, although not the past few years, but the bridle is essential when it comes to controlling the horse, so how can we bridle the tongue before it gets us into trouble? James wrote, “If anyone thinks he is religious and does not bridle his tongue but deceives his heart, this person’s religion is worthless” (James 1:26). To say you’re a Christian and yet deceit is found in our words, that person’s religion is totally worthless. In fact, it’d be better that someone say they’re not a Christian than claim to be one and yet doesn’t bridle their tongue. One of the fruits of the Spirit is self-control and I think that includes controlling the tongue, so “Whoever desires to love life and see good days, let him keep his tongue from evil and his lips from speaking deceit” (1 Pet 3:10).
Words that come out of believers mouths ought to be building up and encouraging one another and not tearing down and destroying, but our words can do either. Solomon wrote that “There is one whose rash words are like sword thrusts, but the tongue of the wise brings healing” (Prov 12:18), so which do we want to be? Surely our words should bring healing and not more pain to someone who’s already hurting. Scripture teaches us that “A gentle tongue is a tree of life, but perverseness in it breaks the spirit” (Prov 15:4). If we realized the total impact that our words have on those around us, particularly our spouse and our children, we might measure our words more carefully, knowing “The tongue of the wise commends knowledge, but the mouths of fools pour out folly” (Prov 15:2).
Maybe you know someone that talks out of both sides of their mouth, or they speak well of someone when they’re there in the room, but when they leave, they become the focus of gossip. It’s amazing that someone may tell you, “God bless you,” but their words betray their heart when they speak ill of you when you’re not around. Jesus said, “the things that come out of the mouth come from the heart, and these things defile a man” (Matt 15:18), so it is “out of the heart come evil thoughts, murder, adultery, sexual immorality, theft, false witness, slander” (Matt 15:19), and these thoughts usually come out as words. People that have a “forked tongue” tend to have hearts full of deceit and they live in duplicity. After a time, their credibility becomes lacking. It is just as James wrote about such duplicity: “With it we bless our Lord and Father, and with it we curse people who are made in the likeness of God” (James 3:9), so clearly, “a lying tongue” is an abomination to God (Prov 6:17). Since “Deacons likewise must be dignified, not double-tongued” (1 Tim 3:8a), neither should we be…deacon or lay member.
We all need God’s help in trying to tame our tongue. We can’t do it alone. How can I say that? Because James already wrote that “no human being can tame the tongue. It is a restless evil, full of deadly poison” (James 3:8). No human can but God can help us…and that’s where we need our help in controlling the tongue. It’s not a matter of self-will or human will power, but yielding to the Holy Spirit and taking great caution in speaking to one another. Why not use that tongue to praise God. The psalmist wrote, “I cried to him with my mouth, and high praise was on my tongue” (Psalm 66:17), which is the reason the psalmist said that “my tongue will talk of your righteous help all the day long” (Psalm 71:24).
When you’re praising God in private prayer and worship and praising God for His goodness before others, you’ll have no urge to hurt people with your words. Use the tongue to build up others and not tear them down. Today, we need to hear a good word from others…more than ever, so there is no greater use for the tongue than to speak in love. In time, every tongue will give God praise and acknowledge that Jesus Christ is Lord. It is as the Apostle Paul wrote, “As I live, says the Lord, every knee shall bow to me, and every tongue shall confess to God” (Rom 14:11). Those are the sweetest words ever uttered by the otherwise deceitful and deadly tongue.
Here is some related reading for you: 7 Good Bible Verses About Taming the Tongue 
Resource – Scripture quotations are from The Holy Bible, English Standard Version® (ESV®), Crossway Bibles. (2007). ESV: Study Bible: English standard version. Wheaton, Ill: Crossway Bibles. Used by permission. All rights reserved.