'Tongue' in the Bible

If a man thinks that he is scrupulously religious, although he is not curbing his tongue but is deceiving himself, his religious service is worthless.

In the same way the tongue is an insignificant part of the body, but it is immensely boastful. Remember how a mere spark may set a vast forest in flames.

And the tongue is a fire. That world of iniquity, the tongue, is placed within us spotting and soiling our whole nature, and setting the whole round of our lives on fire, being itself set on fire by Gehenna.

But the tongue no man or woman is able to tame. It is an ever-busy mischief, and is full of deadly poison.