The Gospel reading today came from Luke 11. Here's the entire reading:
After Jesus had spoken, a Pharisee invited him to dine at his home. He entered and reclined at table to eat. The Pharisee was amazed to see that he did not observe the prescribed washing before the meal. The Lord said to him, "Oh you Pharisees! Although you cleanse the outside of the cup and the dish, inside you are filled with plunder and evil. You fools! Did not the maker of the outside also make the inside? But as to that is within, give alms, and behold, everything will be clean for you."
The lesson here. We must always work from the inside out, starting with the heart. Similarly, to tell others about God, we must know God ourselves first.