How does God’s love abide in anyone who has the world’s goods and sees a brother or sister in need and yet refuses help? Little children, let us love, not in word or speech, but in truth and action. (1 John 3: 17-18)
Check out the King James Version (which somewhat more literally translates the Greek):
But whoso hath this world’s good, and seeth his brother have need, and shutteth up his bowels of compassion from him, how dwelleth the love of God in him? My little children, let us not love in word, neither in tongue; but in deed and in truth.
In other words, don’t be tight-fisted (the KJV suggests another kind of tightness) when you see people in need. Open up your wallet and help as you can.
The contrast to “in word [only]” is “in deed,” is familiar enough; I think it’s interesting that the parallel to “in word” is “in tongue,” and its contrast is “in truth.” In other words, truth here means action.