filtering God's blessings

The water that I shall give him will become in him a fountain of water springing up into everlasting life —John 4:14

"We are to be fountains through which Jesus can flow as "rivers of living water" in blessing to everyone. Yet some of us are like the Dead Sea, always receiving but never giving, because our relationship is not right with the Lord Jesus. As surely as we receive blessings from Him, He will pour out blessings through us." (Chambers, http://www.rbc.org/utmost/)

This verse (along with John 7:38: "Whoever believes in me, as the Scripture has said, streams of living water will flow from within him.") has never really said much to me personally. Perhaps because I don't recall ever hearing it preached or taught in this way. In fact, if I've heard it referred to at all, it has been to point to God blessing me rather than me channeling God's grace to others.

Maybe instead of "channel" it might be better seen as a "filter." That seems more appropriate since I seem to dillute (and pollute) His message with my own experiences and emotions. What comes from me on most days can't be what God intended...yet, as I've heard, He can work through me anyway.

What if the mail man censored my letters, removing the good news, the colorful adjectives and the exclamation points, inserting how he or she felt that particular day, or decided that my letter didn't need to go to a particular person because of race or class...?