It has been said that people don’t care how much we know until they know how much we care. Whether we are talking to fellow believers or to non-believers, the way we speak has a lot to do with how others hear us. 

First, our speech must be courteous—or in Paul’s words, “always be with grace.” Graceful speech is kind, gentle, helpful, and edifying. Think of God’s grace toward you and let your speech be the same. Second, our speech must be compelling—that is, “seasoned with salt.” We salt our food because it makes the taste appealing; the right amount of salt makes us want to eat more. Our speech should make our listener want to hear more. Third, our speech must be compassionate—we should “know how to answer each one.” That is, we must be able to read the room, to know what another person needs to hear. The Holy Spirit will enable us to meet others’ needs if we follow His lead.

We must know what to say (1 Peter 3:15); equally important is knowing how to say it. 

We have all felt the brazenness of words without emotion, the hollowness, the unaccountable unpersuasiveness, of eloquence behind which lies no love. 
Henry Drummond