Give it away, give it away

Our Lord's instructions to the Apostles in today's Gospel (Matthew 10:7-15) cover a number of topics (great material for a retreat). Today, this verse leapt out at me:

Without cost you have received;
without cost you are to give.

What expectations do we have when we share our faith, either by word or by deed?

Do these expectations constitute a "hidden cost" that we impose? Do we sometimes hold back when we think these expectations will not be met?

Without cost you have received;
without cost you are to give.