Matthew 12:34
Offspring of vipers, how can you, being evil, speak good things? For out of the abundance of the heart the mouth speaks.
Acts 20:30
and of yourselves men will arise speaking perverse things, to draw away disciples after them.
1 Timothy 5:13
and at the same time also, being idle, they learn to go from house to house, and not only are they idle, they are also tattlers and mischief makers, saying what they ought not.
Titus 1:10-11
For there are many disorderly wranglers and deceivers, especially those of the circumcision,
James 1:21
Wherefore, laying aside all filthiness and abounding vice, receive with meekness the engrafted word, which is able to save your souls.
James 3:6
And the tongue is a fire, the tongue is made a world of wickedness among our members, it defiles the whole body and sets on fire the course of nature and is set on fire by hell.