Verse 16 is awesome. It's Jesus basic method of evangelism: "Live so that they will see the good things you do and will praise your father in heaven." There are two keys here. One is obvious: do good things. Lots of them. The way people should be able to recognize that we're connected to God is by all of the good things we do. It always makes me sad to talk to people who wait tables and how they hate waiting on people who just got out of church. They're usually the rudest, most demanding, and least appreciative customers out there. Pretty sad.
The other part of this verse is that our lives need to be lived in public view of non-believers. If we surround ourselves with Christians and all the good things we do are for those who already believe, how will anyone ever be able to see it. We have this typical mindset that says once you meet my criteria, then we can hang out and be friends. Pretty pathetic. JM