Proverbs 16

Verses 1, 3 and 9:

"The plans of the heart belong to man, but the answer of the tongue is from the Lord."
"Commit your work to the Lord, and your plans will be established."

"The heart of man plans his way, but the Lord establishes his steps."

We make lots of plans from day to day, but don't stop often enough to include God in them.  We fly off on our own steam and willpower, and forget to say, "If the Lord wills" (James 4:15).  God's purpose will be established, not yours, so focus on that, even as you plan the rest of today, and tomorrow.  This proverb (and Matthew 6:34) do not forbid planning, but we must hold such plans loosely and seek first God's kingdom.

Verses 21, 23-24:
"The wise of heart is called discerning, and sweetness of speech increases persuasiveness.
The heart of the wise makes his speech judicious and adds persuasiveness to his lips.
Gracious words are like a honeycomb, sweetness to the soul and health to the body."

So these verses equate discernment and judiciousness with sweet speech that persuades.  This can be hard to distinguish from manipulative speech, and the only real difference might be the intent.  If you are good with words, do you use them and move others to pursue your own agenda, or trying to guide someone else to godliness?