The length of time it takes you to say something diminishes the potency of what you say exponentially.
Proverbs 10:20-22 (The Message)
20 The speech of a good person is worth waiting for;
the blabber of the wicked is worthless.
21 The talk of a good person is rich fare for many, but chatterboxes die of an empty heart.
And the Bible tells us to keep to the point.
1 Timothy 6:20 (The Message)
20-21And oh, my dear Timothy, guard the treasure you were given! Guard it with your life. Avoid the talk-show religion and the practiced confusion of the so-called experts. People caught up in a lot of talk can miss the whole point of faith.
So say what you mean and mean what you say. The point is to express yourself in a few words. You will influence people more than if you babble on and on and on and on and on . . .
And the best advice is to back it up with action. Be a living example of the influence of Jesus Christ.