For every kind of wild beasts and birds and reptiles and animals from the sea is tamed and has been tamed by human kind,

but the tongue no man is able to tame. It is a restless evil; it is full of deadly poison.

Tiago 3:7,8

9 Therefore, God has highly exalted him and has graciously given him the name which is above every name,

10 that at the name of Jesus every knee may bow, of beings in heaven and those on earth and those under the earth,

11 and every tongue confess that Jesus Christ is Lord, to the glory of God the Father.

Filipenses 2:9-11

IF I speak with the tongues of men and of angels, but have not love, I have become sounding brass or a clanging cymbal.

1 Coríntios 13:1

For in many ways we all stumble. If any one never stumbles in his talk, he is a perfect man, able to bridle also the whole body.

Tiago 3:2

I tell you, for every idle word that men speak they will give full account in the day of judgment,

for from your words you will be justified and from your words you will be condemned."

Mateus 12:36,37

9 With it we bless the Lord our Father and with it we curse the men who are made in the image of God.

10 From the same mouth come blessing and cursing. This, my brethren, should not be so.

11 Does a spring pour out from the same opening sweet water and bitter?

12 Can a fig tree, my brethren, bear olives, or a vine figs? No more can salt water yield fresh water.

Tiago 3:9-12

If any one thinks himself religious while he does not bridle his tongue, but deceives his own heart, that man's religion is worthless.

Tiago 1:26

3 If we put bits into the horses' mouths to make them obey us, we turn about their whole bodies.

4 See the ships; great as they are and driven by violent winds, they are turned about by a very small rudder wherever the desire of the helmsman chooses.

5 Just so the tongue is a small member, but boasts of great things. Think how small a fire may be and yet how vast the forest that it may set ablaze.

6 And the tongue is a fire, a world of wickedness. The tongue stands among our members as that which spots the whole body and sets on fire the wheel of nature and is itself set on fire by Gehenna.

Tiago 3:3-6