Whenever I watch a movie I have seen before, but one of my kids is seeing it for the first time, it is like a brand new experience of the movie. I almost feel like I have never seen it before. I watch their expressions, and can see it through their eyes. It is one of my greatest joys of being a parent. It is almost as enjoyable when I read them a book for the first time, and is only less with a book because I have to keep looking at the page and cannot see their faces as much.
There is another experience that has the exact same feeling behind it. It happens when someone comes to St. George and says that he or she is seriously considering the Catholic faith. They have this expression (which I am certain they are unaware of) that says "this stuff is so amazing; why didn't anyone tell me about this before?" It is that joy and wonderment that is an encouragement to my faith. I mean not just in the sense of confirming that someone else thinks like I do, but also that I can see God working in their lives as He worked in mine. I really do "love" looking into the eyes of someone who is just recently discovering that the Catholic faith is true.
This is one of the reasons why God calls all Catholics to tell others about the gospel. He wants every one of us to see those who come to believe. He wants us to experience that joy all over again. He wants us to realize that He is still at work. When was the last time you told someone about the truth of Christ? If you cannot remember, then you are way behind in your duty.
Imagine if speaking the gospel was like saying the Mass: only for a select group chosen for the task. The majority would never be able to see another's heart go through the joy of conversion. God could have done it this way, but has chosen not to do so. Yes, only Bishops can ordain, and you have to be a Priest to say Mass, but evangelism is open to (and required of) everyone of the faithful.
Someone told me recently that when she shifted her thinking about the Catholic Church and realized it was right all along, her whole world opened up to a new reality. Everything changed. Someone else said that the first time he said to himself "maybe the Catholic faith is right after all" that it felt like switching to a new universe. What a joyful thing to see this happen. Our Lord told us, "Go therefore and make disciples of all nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit, teaching them to observe all that I have commanded you; and lo, I am with you always, to the close of the age." He did not, however, add, "and when you do this, you will experience your own joy beyond belief"; but it would have been true if He had.