Naaman was going back to Syria. He was Captain of the Syrian army, and along with that position came certain responsibilities. He was to worship the god of Syria with the King and he was to command the Syrian army in it's battles. Naaman wanted Elisha to pardon his obligations. He could have been a witness to all of Syria that there was a powerful God who could heal their diseases for free, and yet he wanted to worship in secret and keep his position.
As Christians, we should be willing to be a witness for Christ. We should leave the world behind (like Naaman should have left Syria), not make a life in it. We should give up our comforts and positions to obey God and spread the gospel to those who are lost, not worship in secret to secure our lifestyle.
This message gives Christians some things to think about. Are we secretly worshipping Christ while trying to hold onto what we desire from the world? Or are we willing to lay down our lives for the lost so that others can also become healed?