Tiago 3:3-8 - Bíblia Online

Now if we put bits of iron into horses' mouths so that they may be guided by us, we have complete control of their bodies. 
And again ships, though they are so great and are moved by violent winds, are turned by a very small guiding-blade, at the impulse of the man who is using it. 
Even so the tongue is a small part of the body, but it takes credit for great things. How much wood may be lighted by a very little fire! 
And the tongue is a fire; it is the power of evil placed in our bodies, making all the body unclean, putting the wheel of life on fire, and getting its fire from hell. 
For every sort of beast and bird and every living thing on earth and in the sea has been controlled by man and is under his authority; 
But the tongue may not be controlled by man; it is an unresting evil, it is full of the poison of death. 

Tiago 4

Now if we put bits of iron into horses' mouths so that they may be guided by us, we have complete control of their bodies. 
And again ships, though they are so great and are moved by violent winds, are turned by a very small guiding-blade, at the impulse of the man who is using it. 
Even so the tongue is a small part of the body, but it takes credit for great things. How much wood may be lighted by a very little fire! 
And the tongue is a fire; it is the power of evil placed in our bodies, making all the body unclean, putting the wheel of life on fire, and getting its fire from hell. 
For every sort of beast and bird and every living thing on earth and in the sea has been controlled by man and is under his authority; 
But the tongue may not be controlled by man; it is an unresting evil, it is full of the poison of death. 

Tiago 4