Proverbs 18:21 (NKJV) Death and life are in the power of the tongue, And those who love it will eat its fruit.
James 3:10 (NKJV) Out of the same mouth proceed blessing and cursing. My brethren, these things ought not to be so.
James 3: 1-12 (NKJV) My brethren, let not many of you become teachers, knowing that we shall receive a stricter judgment. 2 For we all stumble in many things. If anyone does not stumble in word, he is a perfect man, able also to bridle the whole body. 3 Indeed, we put bits in horses’ mouths that they may obey us, and we turn their whole body. 4 Look also at ships: although they are so large and are driven by fierce winds, they are turned by a very small rudder wherever the pilot desires. 5 Even so the tongue is a little member and boasts great things. See how great a forest a little fire kindles! 6 And the tongue is a fire, a world of iniquity. The tongue is so set among our members that it defiles the whole body, and sets on fire the course of nature; and it is set on fire by hell. 7 For every kind of beast and bird, of reptile and creature of the sea, is tamed and has been tamed by mankind. 8 But no man can tame the tongue. It is an unruly evil, full of deadly poison. 9 With it we bless our God and Father, and with it we curse men, who have been made in the similitude of God. 10 Out of the same mouth proceed blessing and cursing. My brethren, these things ought not to be so.11 Does a spring send forth fresh water and bitter from the same opening? 12 Can a fig tree, my brethren, bear olives, or a grapevine bear figs? Thus no spring yields both salt water and fresh.
Matthew 12:33-37 (NKJV) “Either make the tree good and its fruit good, or else make the tree bad and its fruit bad; for a tree is known by its fruit. 34 Brood of vipers! How can you, being evil, speak good things? For out of the abundance of the heart the mouth speaks. 35 A good man out of the good treasure of his heart[a] brings forth good things, and an evil man out of the evil treasure brings forth evil things. 36 But I say to you that for every idle word men may speak, they will give account of it in the day of judgment. 37 For by your words you will be justified, and by your words you will be condemned.”
James 1:21-26 (NKJV) Therefore lay aside all filthiness and overflow of wickedness, and receive with meekness the implanted word, which is able to save your souls.22 But be doers of the word, and not hearers only, deceiving yourselves.23 For if anyone is a hearer of the word and not a doer, he is like a man observing his natural face in a mirror; 24 for he observes himself, goes away, and immediately forgets what kind of man he was. 25 But he who looks into the perfect law of liberty and continues in it, and is not a forgetful hearer but a doer of the work, this one will be blessed in what he does.26 If anyone among you[b] thinks he is religious, and does not bridle his tongue but deceives his own heart, this one’s religion is useless.
2 Corinthians 10:5 (NKJV) casting down arguments and every high thing that exalts itself against the knowledge of God, bringing every thought into captivity to the obedience of Christ,