Luke 22:32
"But I made supplication for you that your own faith may not fail. And you, when you have turned again, must strengthen your brothers."
Luke 22:43
(And there appeared to him an angel from heaven, strengthening him.)
Ephesians 4:29
From your lips let no evil words come forth, but such as occasion warrants, such as are good for upbuilding and give a blessing to the hearers.
Colossians 4:6
Let your speech be always gracious, with a savor of salt, and learn how to give every man a fitting answer.
Hebrews 12:12
Wherefore lift up your listless hands, strengthen your feeble knees;