We proclaim to you what we have seen and heard, so that you also may have fellowship with us. And our fellowship is with the Father and with his son, Jesus Christ. We write this to make our joy complete.Ryan asked, what does that mean--making our joy complete? And that got me thinking.
John walked and talked with Jesus for three years during his ministry. ("That which... we have heard, which we have seen with our eyes, which we have looked at and our hands have touched...," verse 1.) He knows this eternal life, "which was with the Father and has appeared to us." He has fellowship with the Father and, even though he's now ascended, his son Jesus Christ. It excites him! This is real, this is eternal life, and he wants them to know it too!
When I'm excited about something, it's even better when I find someone else who's excited about it too. When I see an awesome movie, I love to see it again with people who haven't seen it before, in the hope that they'll enjoy it as much as I do. Now we both enjoy it, and we fellowship in it--this enjoyment is something we share. Few people will go to a theater alone, no matter how awesome the movie is. When I see a hilarious YouTube video, I show it to my family and friends. There's a very real sense in which my joy in something is complete with I can rejoice in it with others.
I think that's what John means when he says, "We write this to make our joy complete." He has fellowship with the Father and with his son Jesus Christ. He wants us, reading this, to have it too. May we have the same desire for others, that our joy may be complete!