Colossians 4:6
Your speech should always be favorable, seasoned with salt [i.e., interesting and appropriate], so that you may know how to properly answer each person [you talk with].
1 Peter 3:15
But instead, set aside a place in your hearts where Christ is [in full control as] Lord, and be prepared always to give a suitable reply to every person who asks you for a reason why you have an inner hope. But [be sure you do it] in a meek and respectful way, however.
Mark 9:50
"Salt is good, but if it loses its salty flavor, what will you use to restore it? [i.e., it is difficult to restore the "salt" of sacrificial commitment to God once it is lost]. You should have salt in yourselves [i.e., develop the qualities of preserving, purifying commitment to God], and live peacefully with one another [i.e., instead of in rivalry. See 9:33-34].
Ephesians 4:29
Do not allow unwholesome [Note: The Greek word for "unwholesome" is "rotten, diseased"] language to come from your mouth, but only what is helpful for building up those who need it, so that you can impart favor [i.e., benefit] to those who listen [to you].
Matthew 5:13
"You people are [like] salt on the earth. But if salt loses its flavoring ability, how will it ever get it back again? From then on it would be good for nothing except to be thrown out onto the roadway and walked on by people. [Note: This was mined salt which, when losing its "saltiness" due to exposure to the sun or rain, was simply disposed of by being dumped onto the roadway where people walked].
Colossians 3:16
You should let the message of Christ live in you abundantly [i.e., as individuals and collectively]. Use [much] wisdom in teaching and warning one another with psalms, hymns and spiritual songs, singing with favor [i.e., with thankfulness] in your hearts toward God.
Matthew 12:34-35
You children of snakes! Since you are evil, how do you expect to speak good things? For the mouth speaks what the heart is filled with.
Luke 4:22
So, everyone spoke well of Him and marvelled at the gracious words coming from His mouth. They said, "Is he not Joseph's son?"
Luke 20:20-40
And they kept watching Him, [even] sending informants who pretended to be good [men], in order to get hold of something He said so they could turn Him over to the ruling authority of the governor.