Romans 10:14-15
How then shall they call on him in whom they have not believed? and how shall they believe in him of whom they have not heard? and how shall they hear without one preaching?
Ephesians 4:29
Let no evil word proceed out of your mouth, but that which is good for useful edification, that it may afford benefit to those that hear.
Treasury of Scripture Knowledge
Summary
There is gold, and a multitude of rubies: but the lips of knowledge are a precious jewel.
Bible References
But
Romans 10:14
How then shall they call on him in whom they have not believed? and how shall they believe in him of whom they have not heard? and how shall they hear without one preaching?
Ephesians 4:29
Let no evil word proceed out of your mouth, but that which is good for useful edification, that it may afford benefit to those that hear.